>>> TONIGHT -- A WHOLE NEW RACE FOR PRESIDENT. DEMOCRATS RALLYING AROUND KAMALA HARRIS AFTER JOE BIDEN STEPS ASIDE. THE VICE PRESIDENT GREETED WITH CHEERS IN WHAT IS NOW HER CAMPAIGN HEADQUARTERS IN DELAWARE. IT COMES AS NANCY PELOSI ADDS HER NAME TO THE LIST OF TOP DEMOCRATS BACKING HARRIS, AFTER PRESIDENT BIDEN DROPPED OUT AND ENDORSED HER. >>> IN JUST 24 HOURS HER CAMPAIGN RAKING IN A RECORD $81 MILLION IN DONATIONS. THE QUESTIONS, HOW WILL ALL THIS WORK WITH THE DEMOCRATIC CONVENTION LESS THAN A MONTH AWAY? WHO WILL HARRIS PICK AS A RUNNING MATE? >>> THE SHAKE-UP FORCING THE TRUMP CAMPAIGN TO PIVOT ATTACKS TO HARRIS. J.D. VANCE IN HIS FIRST SOLO DEBUT AS DONALD TRUMP'S RUNNING MATE SAYING HE'S ANNOYED HE WON'T GET TO DEBATE HER AS TO REPUBLICANS DEMAND MR. BIDEN LEAVE OFFICE NOW. >>> THE DIRECTOR OF THE SECRET SERVICE GRILLED ON CAPITOL HILL SAYING, QUOTE, WE FAILED ON THE DAY A GUNMAN TRIED TO ASSASSINATE DONALD TRUMP. >>> THE DISTURBING BODY CAM. AN ILLINOIS WOMAN FATALLY SHOT IN HER HOME AFTER SHE CALLED 911. THE DEPUTY NOW CHARGED WITH MURDER. >>> A HISTORIC TEAM USA HONOR FOR LeBRON JAMES AS SIMONE BILES AND HER TEAMMATES ARRIVE IN PARIS TO BEGIN THEIR QUEST FOR GOLD. >> Announcer: THIS IS NBC "NIGHTLY NEWS" WITH LESTER HOLT. >>> GOOD EVENING. WELCOME. HOW THE POLITICAL UNIVERSE HAS SHIFTED. JUST A DAY AFTER PRESIDENT BIDEN'S EXIT FROM THE PRESIDENTIAL CONTEST, VICE PRESIDENT KAMALA HARRIS RIDING A WAVE OF DEMOCRATIC PARTY ENDORSEMENTS, IS TAKING HER PLACE AS THE FRONTRUNNER FOR THE NOMINATION. FORMER HOUSE SPEAKER NANCY PELOSI NOW AMONG THE BIGGEST NAMES TO THROW HER SUPPORT TO MS. HARRIS WHOSE SUDDEN CANDIDACY HAS ENERGIZED THE DEMOCRATIC PARTY. A PARTY THAT IN RECENT WEEKS WAS GRIPPED BY PANIC OVER ITS FUTURE. >>> STILL, AS THE TRUMP CAMPAIGN SHIFTS ITS MESSAGE, DEMOCRATS ARE FACING URGENCY TO LOCK THE VICE PRESIDENT AS THEIR NOMINEE AND FOR HER TO NAME A RUNNING MATE. SEVERAL FRONTRUNNERS FOR THE NUMBER TWO SLOT EMERGING TONIGHT IN WHAT IS LIKELY TO BE AN EXPEDITED PROCESS. THIS, ALL AS PRESIDENT BIDEN WHO SET THIS IN MOTION BY STEPPING ASIDE PLEDGED HE'LL CAMPAIGN FOR HIS VICE PRESIDENT. KELLY O'DONNELL WITH THE LATEST DEVELOPMENTS. >> Reporter: A WHIRLWIND DAY FOR VICE PRESIDENT KAMALA HARRIS, VISITING HEADQUARTERS IN WILMINGTON, THE PRESIDENT'S HOMETOWN FOR A CAMPAIGN THAT NOW BEARS HER NAME. PRESIDENT BIDEN AT HOME WITH COVID PHONED IN TO THE CAMPAIGN TEAM LATE TODAY. >> I'M HOPING YOU'LL GIVE EVERY BIT OF YOUR HEART AND SOUL THAT YOU GAVE TO ME TO KAMALA. I WANT YOU TO KNOW, I WON'T BE ON THE TICKET, BUT I'M STILL GOING TO BE FULLY ENGAGED. >> Reporter: AN EXTRAORDINARY CAMPAIGN RESET. AFTER THE PRESIDENT ENDED HIS OWN RUN SUNDAY AND ENDORSED HARRIS TO FINISH THE RACE TO NOVEMBER. >> IT'S MY GREAT HONOR TO HAVE JOE'S ENDORSEMENT IN THIS RACE. IT'S MY INTENTION TO GO OUT AND EARN THIS NOMINATION, AND TO WIN. >> Reporter: HARRIS IS NOT YET THE OFFICIAL NOMINEE, THOUGH SHE APPEARS ON HER WAY. AIDES SAID SHE SPENT TEN HOURS SUNDAY MAKING ABOUT 100 CALLS TO LINE UP SUPPORT. SOUTH CAROLINA DEMOCRAT JAMES CLYBURN TOUTING A RESHAPED RACE. >> SHE'S WELL-EQUIPPED TO PROSECUTE -- I WANT TO EMPHASIZE -- TO PROSECUTE THE CASE AGAINST DONALD TRUMP. >> Reporter: THE ENDORSEMENT OF FORMER SPEAKER NANCY PELOSI WHO WRITES, WE MUST UNIFY AND CHARGE FORWARD. BUILDING ON ENDORSEMENTS FROM THE CLINTONS, CALIFORNIA GOVERNOR GAVIN NEWSOM AND THE CONGRESSIONAL BLACK CAUCUS. TODAY, TOP HOUSE DEMOCRAT HAKEEM JEFFRIES SAID HE AND SENATOR SCHUMER EXPECT TO MEET WITH HARRIS SOON. >> SHE'S EXCITED THE HOUSE DEMOCRATIC CAUCUS AND SHE'S EXCITING THE COUNTRY. >> Reporter: SOME HARRIS SUPPORTERS DESCRIBE SEEING RELUCTANCE AROUND HER POTENTIAL NOMINATION. >> BEHIND CLOSED DOORS, WHILE I WON'T NAME NAMES, PEOPLE WERE LIKE IT CAN'T BE THE VICE PRESIDENT. >> Reporter: ALL OF IT AFTER THE PRESIDENT'S STUNNING ANNOUNCEMENT THAT FOR THE BEST INTEREST OF MY PARTY AND THE COUNTRY, HE WOULD STAND DOWN. A STATEMENT THAT SURPRISED MUCH OF HIS OWN CAMPAIGN STAFF. IN HARRIS' FIRST PUBLIC APPEARANCE TODAY, A PREPLANNED COLLEGE CHAMPIONS EVENT AT THE WHITE HOUSE, THE VICE PRESIDENT HONORED HIS PUBLIC SERVICE. >> JOE BIDEN'S LEGACY OF ACCOMPLISHMENT OVER THE PAST THREE YEARS IS UNMATCHED IN MODERN HISTORY. >> Reporter: HIS DECISION APPEARED TO UNLOCK PRAISE AND APPRECIATION AFTER A FEW AGONIZING WEEKS WHEN ABOUT 40 ELECTED DEMOCRATS PUSHED HIM TO LEAVE THE RACE AND HE RESISTED. >> I AM RUNNING, AND WE'RE GONNA WIN! I'M NOT GOING TO CHANGE THAT. ARE YOU ALL IN? I'M ALL IN! >> Reporter: DURING A WEEKEND OF DECISION, DEALING WITH COVID IN DELAWARE, SOURCES FAMILIAR WITH THE SITUATION TELL NBC NEWS THE PRESIDENT FELT HURT, ANGRY AND BETRAYED BY ALLIES LIKE BARACK OBAMA AND NANCY PELOSI WHO HE BELIEVES TURNED ON HIM. ONE CLOSE ADVISER UPSET SAYING THE PRESIDENT WAS TREATED DISRESPECTFULLY. >> KELLY, LET'S TURN BACK THE CLOCK FOR A MOMENT. TOP DEMOCRATIC DONORS HAVE BEEN DEMANDING THAT PRESIDENT BIDEN DROP OUT. NOW THE HARRIS CAMPAIGN IS SEEING A BIG FUND-RAISING BOOST. >> Reporter: YOU'RE RIGHT, LESTER. THOSE DONORS THREATENED TO HOLD BACK MONEY. NOW THE HARRIS CAMPAIGN SAID IT RAISED $81 MILLION SINCE THE PRESIDENT LEFT THE RACE AND ENDORSED THE VICE PRESIDENT. LESTER? >> KELLY O'DONNELL, AT THE WHITE HOUSE, THANK YOU. >>> AMONG THE CHALLENGES HARRIS FACES AS A PRESIDENTIAL CANDIDATE, PICKING A RUNNING MATE AND FASHIONING HER BACKGROUND BEFORE AND DURING HER VICE PRESIDENCY INTO A NARRATIVE THAT WILL APPEAL TO VOTERS. HERE'S HALLIE JACKSON. >> Reporter: VICE PRESIDENT HARRIS WORKING THE ROOM TODAY TRYING TO CAPITALIZE ON THIS CRITICAL MOMENT AND RE-INTRODUCE HERSELF AS A PRESIDENTIAL CANDIDATE. THE LATEST TWIST IN A JOURNEY THAT'S TAKEN HER FROM THE WEST COAST TO THE WHITE HOUSE. THE DAUGHTER OF JAMAICAN AND INDIAN IMMIGRANTS SHAPED BY HER PARENTS' CIVIL RIGHTS ACTIVISM, HARRIS REFLECTING ON HER CHILDHOOD WHILE RUNNING FOR PRESIDENT IN 2019, MEMORABLY CRITICIZING HER FUTURE RUNNING MATE JOE BIDEN FOR HIS RECORD ON BUSSING. >> THERE WAS A LITTLE GIRL IN CALIFORNIA WHO WAS PART OF THE SECOND CLASS TO INTEGRATE HER PUBLIC SCHOOL AND SHE WAS BUSSED TO SCHOOL EVERY DAY. THAT LITTLE GIRL WAS ME. >> Reporter: HARRIS ROSE TO BECOME CALIFORNIA'S FIRST BLACK AND SOUTH ASIAN ATTORNEY GENERAL IN 2010 BEFORE HER SENATE RUN SIX YEARS LATER WHERE SHE TURNED CONGRESSIONAL HEARINGS INTO CROSS-EXAMINATIONS. >> I'M ASKING YOU A VERY DIRECT QUESTION. >> Reporter: DEMOCRATIC ALLIES ARGUING HARRIS' BACKGROUND AS A PROSECUTOR HELPS HER PRESS THE CASE AGAINST FORMER PRESIDENT TRUMP AND HIS FELONY CONVICTIONS. NOW HARRIS WILL RUN ON THE BIDEN/AGENDA ON THE ECONOMY, INFLATION AND IMMIGRATION AFTER HARRIS WAS TAPPED TO LEAD THE WHITE HOUSE RESPONSE TO ROOT CAUSES OF THE BORDER CRISIS. >> WE'VE BEEN TO THE BORDER. WE'VE BEEN TO THE BORDER. >> YOU HAVEN'T BEEN TO THE BORDER. >> AND I HAVEN'T BEEN TO EUROPE. I DON'T UNDERSTAND THE POINT YOU'RE MAKING. I'M NOT DISCOUNTING THE IMPORTANCE OF THE BORDER. >> Reporter: ON THE ISSUE OF ABORTION ACCESS, WHICH DEMOCRATS THINK COULD MOBILIZE VOTERS COME NOVEMBER, HARRIS HAS BEEN AMONG THE ADMINISTRATION'S LOUDEST VOICES ADVOCATING FOR PROTECTIONS. >> HOW DARE THESE ELECTED LEADERS BELIEVE THEY'RE IN A BETTER POSITION TO TELL WOMEN WHAT THEY NEED. >> Reporter: NOW THE ONE-TIME RUNNING MATE SET TO SELECT A RUNNING MATE OF HER OWN, RACKING UP ENDORSEMENTS FROM THOSE SPECULATED TO BE ON THE SHORT LIST, LIKE CALIFORNIA'S GAVIN NEWSOM AND KENTUCKY GOVERNOR ANDY BESHEAR. >> THE CONTRAST BETWEEN HER AND THOSE ON THE OTHER SIDE COULDN'T BE CLEARER. >> Reporter: OTHER POSSIBLE CONTENDERS PENNSYLVANIA'S JOSH SHAPIRO, ARIZONA'S MARK KELLY AND NORTH CAROLINA'S ROY COOPER. >> I WANT TO MAKE SURE KAMALA HARRIS WINS. >> Reporter: TONIGHT MULTIPLE SOURCES TELL NBC NEWS ERIC HOLDER HAS BEEN TAPPED TO LEAD THE VETTING PROCESS FOR THE VICE PRESIDENT'S POTENTIAL RUNNING MATES. LESTER? >> HALLIE JACKSON, THANK YOU. LAURA JARETT JOINING ME NOW. THERE'S NOT A LOT OF TIME HERE. >> NO. THERE'S A BIG PUSH TO BUTTON UP THINGS SOON OTHERWISE DEMOCRATS CAN MISS KEY STATE DEADLINES. OHIO HAS THE FIRST DEADLINE ON AUGUST 7th. THE DEMOCRATIC CONVENTION IS THE 19th. THAT'S WHY THERE'S AN URGENCY TO HOLD A ROLL CALL VOTE THAT WOULD NOMINATE THE PARTIES' CANDIDATES. NOT JUST THE PRESIDENT. THE VICE PRESIDENT HAS BEEN CERTIFIED TO APPEAR ON THE BALL LET BALLOT IN TIME. THAT DOESN'T LEAVE VICE PRESIDENT KAMALA HARRIS AS LOT OF TIME. >> THANK YOU, LAURA. >>> LET'S LOOK AT THIS FROM THE ANGLE OF THE TRUMP CAMPAIGN. IT'S A RESET FOR THEM AS WELL. A NEW OPPONENT, BUT THE CAMPAIGN SAID THEY'VE SPENT WEEKS PREPARING FOR IT. GARRETT HAAKE WITH THE NEW REPORTING. >> Reporter: AFTER 615 DAYS FOCUSSED ON JOE BIDEN, THE TRUMP CAMPAIGN SHIFTING NOW FOR A LIKELY SHOWDOWN WITH VICE PRESIDENT HARRIS. >> I GUESS SHE'S GOING TO RUN FOR PRESIDENT NOW. >> Reporter: MR. TRUMP'S RUNNING MATE J.D. VANCE MOCKING HARRIS AT A RALLY IN OHIO. >> I WAS TOLD I WAS GOING TO DEBATE KAMALA HARRIS. NOW PRESIDENT TRUMP GETS TO DEBATE HER? I'M KIND OF PISSED OFF ABOUT THAT. >> Reporter: THE TRUMP CAMPAIGN TELLS NBC NEWS THEY'VE PREPARED FOR WEEKS TO RUN AGAINST HARRIS. THE FORMER PRESIDENT EXPANDING HIS ATTACKS ON HARRIS. >> SHE'S NOT A COMPETENT PERSON. SHE SHOULDN'T BE PRESIDENT. SHE'S LAUGHED AT ALL OVER THE WORLD. >> Reporter: HER ELEVATION COULD CHANGE SOME OF THE FUNDAMENTAL DYNAMICS OF THE RACE, WITH TRUMP NOW THE OLDEST CANDIDATE. RUNNING A POSSIBLE HARRIS-LED TICKET COULD RE-ENERGIZE YOUNGER AND DIVERSE VOTERS. A POLL TAKEN IN THE LAST 24 HOURS SHOWS HARRIS DOING BETTER THAN BIDEN AGAINST MR. TRUMP, THE RACE WITHIN THE MARGIN OF ERROR AND PREVIEWING A NEW TRUMP LINE OF ATTACK, A GROUP RELEASING THIS AD ACCUSING HARRIS OF A COVERUP. >> KAMALA WAS IN ON IT. SHE COVERED UP JOE'S OBVIOUS MENTAL DECLINE. >> OUR PRESIDENT IS IN GOOD SHAPE, GOOD HEALTH. >> Reporter: THE GOP ALSO NOT LETTING UP ON PRESIDENT BIDEN WITH TOP REPUBLICANS, INCLUDING THE HOUSE SPEAKER, DEMANDING HE STEP DOWN NOW. >> THE PRESIDENT SHOULD RESIGN. THE REASON IS, IF EVERYONE ACKNOWLEDGES HE'S INCAPABLE OF RUNNING A CAMPAIGN, THEN HE'S CLEARLY INCAPABLE OF RUNNING THE COUNTRY. I MEAN, HE HAS THE NUCLEAR CODES. >> Reporter: VANCE ARGUING ANY DEMOCRATIC VOTER TURNED OFF BY WHAT HE CALLED A COUP AGAINST PRESIDENT BIDEN SHOULD VOTE FOR THE REPUBLICAN TICKET INSTEAD. IT'S AN ARGUMENT THE TRUMP CAMPAIGN HOPES TAKES TRACTION IN VIRGINIA. A STATE THAT HASN'T VOTED FOR A REPUBLICAN FOR PRESIDENT SINCE 2004. LESTER? >> GARRETT HAAKE, THANK YOU. >>> IT'S ALL SENDING SHOCK WAVES THROUGH THE BATTLEGROUND STATES. ZINHLE ESSAMUAH IS IN PENNSYLVANIA WHERE SHE'S ASKING VOTERS WILL IT CHANGE HOW THEY CAST THEIR BALLOTS. >> Reporter: REACTION TONIGHT IN PENNSYLVANIA AFTER A MAJOR SHIFT IN THE RACE TO THE WHITE HOUSE. >> I WAS SURPRISED BECAUSE HE SAID HE WAS STAYING IN AND I WAS SUPPORTING HIM. >> Reporter: THE BATTLEGROUND STATE IS CRITICAL WITH 19 ELECTORAL VOTES UP FOR GRABS AND POLLING CLOSE. WE SPOKE TO THREE DEMOCRATIC VOTERS AND ONE UNDECIDED. >> WHAT WENT THROUGH YOUR MIND WHEN YOU HEARD THE PRESIDENT WAS NOT GOING TO RUN? >> I ALMOST FELT RELIEF. THERE'S BEEN SO MUCH BACK AND FORTH. >> SPEAKING TO A LOT OF OTHER GEN-Z VOTERS, FOR A LONG TIME WE'VE BEEN FEELING DISENFR DISENFRANCHISED. >> Reporter: NBC POLLING SHOWING 83% OF VOTERS UNDER 34 WANTED A DIFFERENT NOMINEE. THIS FIRST TIME VOTER WHO WAS UNDECIDED, NOW WEIGHING NEW OPTIONS. >> EVEN IN HER FOUR YEARS AS VICE PRESIDENT, DIDN'T HEAR MUCH FROM HER EXCEPT THE OCCASIONAL IMMIGRATION THING. >> Reporter: VOTERS TODAY RAISING CONCERNS ABOUT KEY ISSUES LIKE ABORTION, THE ECONOMY AND CIVIL RIGHTS. >> AS A BLACK WOMAN, MOTHER, WIFE, I WORRY ABOUT MY CHILDREN. >> YOU'RE A MOTHER. YOUR DAUGHTER IS RIGHT NEXT TO YOU. DO YOU WORRY ABOUT THOSE THINGS? >> DEFINITELY. >> IF YOU HAD TO VOTE TODAY, WHO WOULD YOU VOTE FOR? >> KAMALA HARRIS. >> KAMALA HARRIS WITHOUT A DOUBT. >> KAMALA HARRIS. >> Reporter: NICK SAYS HE WANTS TO LEARN MORE ABOUT HARRIS, BUT HAS RESERVATIONS. >> IT'S GOING TO BE REALLY HARD TO PULL OFF THE CAMPAIGN IN THIS SHORT OF TIME IN THE NEXT MONTH. SHE HAS TO CONVINCE EVERYONE IN THE PARTY TO UNITE BEHIND HER. >> Reporter: ZINHLE ESSAMUAH, NBC NEWS, PHILADELPHIA, PENNSYLVANIA. >>> NINE DAYS AFTER THE ATTEMPTED ASSASSINATION OF FORMER PRESIDENT DONALD TRUMP, THE HEAD OF THE SECRET SERVICE FACED CALLS TO RESIGN AND HEATED QUESTIONING ABOUT THE SECURITY LAPSES THAT DAY. RYAN NOBLES HAS DETAILS. >> Reporter: FOR SECRET SERVICE DIRECTOR KIMBERLY CHEATLE, IT WAS A BIPARTISAN UNLOADING. >> NOT ONLY SHOULD YOU RESIGN, IF YOU REFUSE, PRESIDENT BIDEN SHOULD FIRE YOU. >> IF YOU HAVE AN ASSASSINATION ATTEMPT ON A PRESIDENT, FORMER PRESIDENT OR A CANDIDATE, YOU NEED TO RESIGN. >> WOULD YOU LIKE TO USE MY FIVE MINUTES TO DRAFT YOUR RESIGNATION LETTER? YES OR NO. >> NO, THANK YOU. >> Reporter: CHEATLE APPEARING BY SUBPOENA AND TESTIFYING UNDER OATH DIRECTLY ADDRESSED THE ATTEMPTED ASSASSINATION OF FORMER PRESIDENT DONALD TRUMP. >> ON JULY 13th WE FAILED. AS A DIRECTOR OF THE UNITED STATES SECRET SERVICE, I TAKE FULL RESPONSIBILITY FOR ANY SECURITY LAPSE OF OUR AGENCY. >> Reporter: FACING OFF WITH MEMBERS OF CONGRESS, SHE LEFT MANY FRUSTRATED. >> WAS THE GUN ALREADY ON THE ROOF OR DID THE SHOOTER CARRY THE GUN UP WITH HIM? >> I DO NOT HAVE THAT INFORMATION AT THIS TIME. >> Reporter: CHEATLE PRESSED ON WHY THE BUILDING THOMAS MATTHEW CROOKS FIRED SHOTS FROM, LESS THAN 150 YARDS FROM THE STAGE, WASN'T SECURE. >> WASN'T THAT BUILDING WITHIN THE PERIMETER THAT SHOULD BE SECURED? DO WE AGREE WITH THAT? >> THE BUILDING WAS OUTSIDE OF THE PERIMETER ON THE DAY OF THE VISIT. IT'S ONE OF THE THINGS THAT DURING THE INVESTIGATION WE WANT TO LOOK AT AND DETERMINE WHETHER OR NOT OTHER DECISIONS SHOULD HAVE BEEN MADE. >> Reporter: THE DIRECTOR ALSO SPEAKING TO REPORTS THAT CROOKS HAD BEEN PHOTOGRAPHED AND IDENTIFIED AS SUSPICIOUS, WELL BEFORE MR. TRUMP TOOK THE STAGE. >> WHY WAS HE ALLOWED TO TAKE THE STAGE WITH A SUSPICIOUS PERSON HAVING BEEN IDENTIFIED? >> I APPRECIATE THE QUESTION. THE DETAIL HAD BEEN PASSED INFORMATION THAT THERE WAS A THREAT. THE DETAIL WOULD NEVER HAVE BROUGHT THE FORMER PRESIDENT OUT ON TO STAGE. >> YOU DISTINGUISH BETWEEN SOMEONE WHO IS SUSPICIOUS AND SOMEONE WHO'S THREATENING? >> I DO. >> Reporter: CHEATLE SAID CROOKS WHO WAS SEEN MINUTES BEFORE FIRING SHOTS WAS INDEED A THREAT UNTIL SECONDS BEFORE THE GUNFIRE BEGAN AND SAID, EVEN THOUGH THE TRUMP CAMPAIGN HAD BEEN DENIED REQUESTS FOR ADDITIONAL SECRET SERVICE RESOURCES IN THE PAST TWO YEARS, THAT WAS NOT CORRECT ON THE DAY OF THE SHOOTING. >> ON JULY 13th THE DETAIL -- THE ASSETS REQUESTED FOR THAT DAY WERE GIVEN. >> Reporter: AT THE END OF TODAY'S HEARING THE TOP REPUBLICAN AND DEMOCRAT ON THE COMMITTEE SENT DIRECTOR CHEATLE A LETTER TELLING HER IT IS TIME FOR HER TO RESIGN, A CALL THAT SHE'S SO FAR RESISTING. LESTER? >> RYAN NOBLES, THANK YOU. >>> COMING UP, SHE CALLED 911 FOR HELP. WHEN DEPUTIES RESPONDED, THEY SHOT HER. NOW ONE OF THEM HAS BEEN CHARGED. >>> THERE IS OUTRAGE IN ILLINOIS TONIGHT AFTER A WOMAN WAS FATALLY SHOT IN HER HOME BY A DEPUTY AFTER SHE CALLED 911 TO REPORT AN INTRUDER. AUTHORITIES TODAY RELEASING THE BODY CAM. MAGGIE VESPA WITH THE VIDEO. WE HAVE TO WARN YOU, IT IS DISTURBING. >> YOU CALLED US. >> Reporter: 36-YEAR-OLD SONYA MASSEY IS SEEN ON BODY CAMERA VIDEO OPENING HER FRONT DOOR TO HER SPRINGFIELD, ILLINOIS, HOME FOR THE FINAL TIME. AFTER INVESTIGATORS SAY IN THE EARLY MORNING HOURS OF JULY 6th SHE CALLED 911 ABOUT A POSSIBLE INTRUDER. MASSEY AT TIMES SEEMING CONFUSED. >> I'M TRYING TO HELP Y'ALL. >> WHAT DO YOU NEED HELP WITH? >> NOTHING, I JUST -- PLEASE GOD. PLEASE GOD. >> Reporter: HALFWAY INTO THE 36-MINUTE CLIP RELEASED TODAY BY ILLINOIS STATE POLICE, MASSEY WALKS TO HER STOVE AND PICKS UP A POT OF BOILING WATER. IT'S DIFFICULT TO HEAR WHAT SHE SAYS. THAT'S WHEN THE DEPUTY ON SCREEN IDENTIFIED AS SEAN GRAYSON REPLIES. >> DROP THE POT. DROP IT. [ GUNFIRE ] >> SHOTS FIRED! SHOT FIRED! >> Reporter: OFFICIALS SAYING MASSEY, A MOTHER OF TWO, WAS SHOT IN THE HEAD. >> I'M NOT TAKING A POT OF BOILING WATER TO MY FACE. >> Reporter: VIDEO OF HER BODY BLURRED BY POLICE. A GRAND JURY INDICTING DEPUTY GRAYSON ON CHARGES OF FIRST DEGREE MURDER. GRAYSON'S LAWYER REFUSING TO COMMENT. >> I WANT JUSTICE FOR MY BABY. >> Reporter: MASSEY'S FAMILY ALONGSIDE CIVIL RIGHTS ATTORNEY BEN CRUMP. >> SHE NEEDED A HELPING HAND, NOT A BULLET TO THE FACE. >> Reporter: PRESIDENT BIDEN SAYING THEY DESERVE JUSTICE, CALLING IT AN UNTHINKABLE AND SENSELESS LOSS. MAGGIE VESPA, NBC NEWS. >>> WE'LL TAKE A BREAK HERE. DAYS AFT >>> IT'S BEEN THREE DAYS NOW SINCE THE GLOBAL COMPUTER MELTDOWN AND TODAY DELTA AIRLINES IS STILL STRUGGLING, CANCELING HUNDREDS OF FLIGHTS NATIONWIDE. TOM COSTELLO JOINS US. TOM, WHAT'S THE LATEST? >> Reporter: 22% OF FLIGHTS CANCELED TODAY, 840. THAT MEANS 7,000 SINCE LAST FRIDAY. WE'VE SEEN LONG LINES AT AIRPORTS NATIONWIDE, LINES THAT STRETCH FOR HOURS. PEOPLE ON TELEPHONE HOLD FOR NINE HOURS AND MORE. MANY COMPLAINED THAT DELTA HAS BEEN STRUGGLING FOLLOWING THE COMPUTER OUTAGE THAT MANY AIRLINES STRUGGLED WITH, BUT THEY GOT BACK UP OVER THE WEEKEND. DELTA SAID ITS CREW SCHEDULING COMPUTER WENT DOWN OVER THE WEEKEND. THAT'S WHY IT'S STRUGGLING TO CATCH UP IN THE BUSIEST TRAVEL PERIOD IN HISTORY. DELTA SAID IT COULD TAKE A COUPLE MORE DAYS TO GET FULLY BACK UP AND OPERATIONAL. LESTER? >> TOM, THANKS. >>> PARIS AS YOU'VE >>> FINALLY, JUST FOUR DAYS UNTIL THE OPENING CEREMONY. AS STEPHANIE GOSK REPORTS, WHEN TEAM USA MAKES ITS ENTRANCE IN PARIS, THEY'LL BE LED BY AN NBA SUPERSTAR. >> Reporter: IN THE HEART OF PARIS, THE OLYMPIC GAMES HAVE TAKEN OVER. ON FRIDAY THE OPENING CEREMONY WILL MAKE HISTORY, OUTSIDE THE CONFINES OF A STADIUM FOR THE FIRST TIME AND ON THE WATER. THE FLOATING CELEBRATION DOWN THE RIVER SEINE. TODAY TEAM USA ANNOUNCED THAT LeBRON JAMES WILL HAVE THE HONOR OF HOLDING THE FLAG. >> YOU GET TO WAVE THE FLAG IN PARIS, MY MAN. >> Reporter: FELLOW OLYMPIAN STEPH CURRY GIVING HIM THE NEWS. >> AN ABSOLUTE HONOR. >> Reporter: FOR TWO WEEKS ATHLETES WILL COMPETE ACROSS THE CITY, MANY ON THE DOORSTEP OR INSIDE SOME OF THE MOST RECOGNIZABLE LANDMARKS IN THE WORLD. IN THE 17th CENTURY LOUIS XVI TURNED THIS PLACE INTO A PALACE. IN THE 18th CENTURY LOUIS XVII WAS KICKED OUT DURING THE FRENCH REVOLUTION. NOW IT'S THE SETTING FOR THE EQUESTRIAN EVENT. THIS COUPLE FROM PENNSYLVANIA HAVE A HORSE IN THE COMPETITION, BRUNO. >> YOU'RE HOPEFUL YOU E WILL GET A MEDAL. >> IT'S VERY STIFF COMPETITION. THE ENGLISH HAVE A VERY STRONG TEAM. >> Reporter: NO MEDAL IS EVER GUARANTEED. FOR THE ATHLETES WHO HAVE MADE IT HERE, ONE THING IS CERTAIN. >> WE DIDN'T GET THIS EXPERIENCE LAST OLYMPICS, SO WE'RE OVERLY HYPED. >> Reporter: THIS IS THEIR CHANCE. STEPHANIE GOSK, NBC NEWS PARIS. >>> THAT IS "NIGHTLY NEWS" FOR THIS MONDAY. THANK YOU FOR WATCHING. I'M LESTER HOLT. PLEASE TAKE CARE OF YOURSELF AND EACH OTHER. GOOD NIGHT.