WASHINGTON — U.S. Vice President Kamala Harris moved quickly on Monday to cement her front-runner status for the Democratic presidential nomination, collecting tens of millions of dollars in donations and winning endorsements of key elected officials in the party. She raised more than $50 million for her campaign in the hours after President Joe Biden stunningly withdrew Sunday from the 2024 contest against former President Donald Trump and endorsed her candidacy. Her campaign’s total was amassed along with a larger haul of more than $80 million collected at ActBlue, the online donation-processing portal used by Democrats. Numerous Democratic officials endorsed the candidacy of the 59-year-old Harris, and no key challengers have announced they will fight her for the nomination. Former House of Representatives Speaker Nancy Pelosi, still an influential figure within Democratic circles, endorsed her ascent to the presidential nomination, with other party leaders in Congress expected to follow. “Today, it is with immense pride and limitless optimism for our country’s future that I endorse Vice President Kamala Harris for president of the United States,” Pelosi said in a statement. “My enthusiastic support for Kamala Harris for president is official, personal and political.” In addition, numerous Democratic governors across the country endorsed Harris, including J.B. Pritzker of Illinois, Gretchen Whitmer of Michigan, Andy Beshear of Kentucky, Wes Moore of Maryland, Gavin Newsom of California, Tim Walz of Minnesota and Tony Evers of Wisconsin. The names of several of them have been floated as possible vice-presidential running mates with Harris although she has made no public comments about who is under consideration. Biden had established the Biden-Harris national campaign headquarters in Wilmington, Delaware, the eastern U.S. city where his longtime home is. Harris is visiting there late Monday to meet with campaign officials. But whether she moves the headquarters back to Washington to be close to the official vice-presidential residence or even swaps out high-level campaign officials was not known in the immediate transformation of her role in the campaign. Democratic officials have yet to settle whether they will hold a virtual presidential nominating contest starting in early August or wait until the Democratic National Convention meets in Chicago from August 19-22 to formally pick a candidate to run against Trump, the Republican nominee. Several state delegations to the convention announced they are supporting Harris for the party’s presidential nomination. Harris was a senator from California, the country’s most populous state, before Biden picked her as his vice-presidential running mate in 2020. She had been running for reelection for another four-year term as Biden’s second in command before he relented to a growing number of calls from Democrats to drop out of the race after his faltering debate performance against Trump in late June. While a Trump-Harris contest wasn’t etched onto ballots yet, the campaign quickly began as news of Biden’s withdrawal from the contest took hold. On Sunday night, a Harris campaign video mocked Trump as “a world leader in temper tantrums” while casting her as a politician “who never loses her cool.” Meanwhile, Trump’s campaign contended that Harris was aware that the 81-year-old Biden was declining mentally and physically. “Kamala was in on it,” the ad said. “She covered up Joe’s obvious mental decline. But Kamala knew Joe couldn’t do the job. So, she did it.” Therefore, the ad claimed, “Kamala owns this failed record.” Harris made her first public appearance since Biden withdrew from the race at a White House tribute early Monday to honor championship college athletic teams from the past year. She did not allude to the coming campaign but praised Biden for his “big heart” and his “deep love of our country.” “I am a firsthand witness,” she said, “that every day, our president, Joe Biden, fights for the American people, and we are deeply, deeply grateful for his service to our nation.”