Credit Jim Wilson/The New York Times
Despite growing calls from Democrats that he drop out of the race, Senator Bernie Sanders said on Sunday that he would continue to fight for the Democratic presidential nomination, refusing to concede it to Hillary Clinton.
Mrs. Clinton earned enough delegates to clinch the nomination last week, but Mr. Sanders has declined to end his campaign or acknowledge her achievement as the first female presidential nominee of a major party. He has contended that he could persuade enough superdelegates, the party leaders who have overwhelmingly backed Mrs. Clinton, to switch their support to him by arguing that he would be the stronger candidate against Donald J. Trump, the presumptive Republican presidential nominee.
That plan became more improbable last week as high-profile Democrats supported Mrs. Clinton. President Obama endorsed her on Thursday, calling her the most qualified candidate ever to seek the White House and imploring Democrats to unite behind her. Vice President Joseph R. Biden Jr. and Senator Elizabeth Warren of Massachusetts, who had stayed out of the race, also endorsed Mrs. Clinton. Senator Jeff Merkley of Oregon, the only senator to endorse Mr. Sanders, told CNN on Friday that he now supports Mrs. Clinton.
Still, after a meeting on Sunday at his home in Burlington, Vt., with some of his top advisers and supporters, Mr. Sanders emerged and told gathered reporters that he had no intention of leaving the race, though he did recognize the long odds he faced.
“We are going to take our campaign to the convention with the full understanding that we are very good at arithmetic and that we know, you know, who has received the most votes up to now,” he said while standing in front of his wife, Jane, and a dozen or so supporters, including Benjamin T. Jealous, a former president of the N.A.A.C.P.; Representative Raul M. Grijalva of Arizona; Nina Turner, a former Ohio state senator; and Bill McKibben, the environmentalist and author.
Graphic: If You Think the Democratic Primary Race Is Close, the 2008 One Was Even Tighter
In recent days, it had been unclear whether Mr. Sanders intended to fight on. After he met with Mr. Obama on Thursday, he said he looked forward to seeing how he could work with Mrs. Clinton “to defeat Donald Trump and to create a government which represents all of us, and not just the one percent.” Then he held a rally that night in Washington, D.C., urging voters to cast ballots for him on Tuesday in the nation’s final primary.
When asked by Chuck Todd on Sunday’s “Meet the Press” on NBC whether he was an “active candidate,” he responded that he wanted to see Mr. Trump defeated.
Mr. Sanders noted that he and Mrs. Clinton planned to meet on Tuesday and that he would ask her “whether she will be vigorous in standing up for working families in the middle class, moving aggressively in climate change, health care for all, making public colleges and universities tuition-free.”
“And after we have that kind of discussion, and after we can determine whether or not we are going to have a strong and progressive platform,” he said, “I will be able to make other decisions.”
There were signs that he was winding down his run. While Mrs. Clinton has been hiring campaign workers, Mr. Sanders began laying off at least half of his campaign staff members last week. He has let go a number of advance staff members who help with campaign logistics, as well as field workers who have been canvassing for votes.
While he is effectively no longer a threat, Mrs. Clinton and the Democrats are counting on Mr. Sanders to eventually get behind her candidacy. He has a loyal base of more than 10 million voters and an enormous donor list that Mrs. Clinton will want to tap into. Some of his supporters say they will not vote for anyone but Mr. Sanders, so Mrs. Clinton’s success may depend on how vocally he supports her.