By Alan Rappeport, Yamiche Alcindor And Jonathan Martin, nytimes.com
Democrats prepared to formally nominate Hillary Clinton for president on Tuesday, looking to move beyond the lingering anger that has brought protests and dissension to their convention this week as they seek to unite behind the first female candidate to represent a major American political party.
Mrs. Clinton will officially become the party’s standard-bearer sometime after 4 p.m., when the delegates plan a roll-call vote on the floor of the convention. Although the conclusion is foregone, the Clinton campaign and that of Senator Bernie Sanders agreed that it would help party unity for Sanders supporters to be heard. In an emotional speech on Monday night, the Vermont senator said he was looking forward to the vote.
The voting is likely to end with a symbolic flourish. A spokesman for Mr. Sanders, Michael Briggs, said he expected that when the roll call was nearly completed, the Vermont delegation could move to make the Clinton nomination unanimous by acclamation.
In 2008, Mrs. Clinton herself moved to stop the voting and nominate Senator Barack Obama, putting the bitterness of their primary fight behind them. This time, Mr. Sanders is not expected to nominate Mrs. Clinton.
Despite hopes for harmony this year, there were signs on Tuesday that the discord that marked the first two days of the convention could persist.
Mr. Sanders again faced boos on Tuesday morning as his restive supporters continued to protest his efforts to persuade them that voting for Mrs. Clinton was the best way to defeat Donald J. Trump, the Republican nominee.
After making the rounds at several breakfasts, Mr. Sanders was met with a loud chorus of jeers from members of the California delegation. The backlash started immediately, with many people in the audience giving Mr. Sanders a thumbs-down sign. But Mr. Sanders was quick to quiet the crowd and chide them for their response.
“It is easy to boo,” he said. “But it is harder to look your kids in the face who would be living under a Donald Trump presidency.”
That seemed to silence most of the audience as he finished his brief remarks. Mr. Sanders insisted that supporting the Democratic ticket this year did not mean giving up on the goals of his campaign.
“What the political revolution means is we keep going,” he said. “We think big, not small. We have the guts to take on the billionaire class.”
At one point during the breakfast with California delegates, a couple of dozen aggressive Sanders supporters burst into loud chanting as Representative Xavier Becerra, Democrat of California, took the stage. Several protesters rushed the stage with signs, trying to block the cameras.
The chants continued even as some Clinton supporters chanted “Hillary! Hillary!” to try to drown out the Sanders supporters. A fight almost broke out when a Sanders activist started screaming that he had been kicked by a woman supporting Mrs. Clinton.
Asked later, several Sanders supporters said they had no idea who was on stage speaking. One woman said she was upset that Mr. Becerra had supported Mrs. Clinton even though his district had voted for Mr. Sanders. Mr. Becerra’s district encompasses downtown Los Angeles and much of heavily Latino East Los Angeles.
Even after Mr. Sanders had left the California delegation gathering, a group of people inside the ballroom at the Marriott interrupted the speakers by chanting “Bernie! Bernie!” One person waved a sign demanding an end to the Trans-Pacific Partnership trade deal.
Earlier Tuesday, Mr. Sanders spoke to delegates from Wisconsin, Montana and Alaska. There, Mr. Sanders was met with tense silence when he tried to make the case for Mrs. Clinton. He started by calling Mr. Trump “the worst, least-prepared candidate for president in my lifetime,” then went on to make his pitch.
“We have got to obviously elect Hillary Clinton,” Mr. Sanders said, as many in the room sat quietly.
He then quickly went on to deliver a line that roused the crowd, saying that his supporters must “stay focused on our issues and force every level of government to represent working people.”
Even as resistance persisted, Mr. Sanders expressed optimism that his supporters would eventually come around while empathizing with their feelings of disappointment.