(Updates throughout with detail of nomination, Tuesday events, Trump comment)

By John Whitesides and Alana Wise

PHILADELPHIA, July 26 (Reuters) - Hillary Clinton was set to become the first woman presidential nominee of a major U.S. party on Tuesday, a historic moment that Democrats hope will help eclipse rancor between supporters of Clinton and her rival in the primary contests, Bernie Sanders.

The party will make its nomination on the second day of a convention that began on Monday with anti-Clinton feeling among die-hard Sanders supporters on full and vocal display.

Sanders, one of the main speakers on the first evening, portrayed Clinton as a fellow soldier in his fight for economic equality, but some of his supporters booed the mere mention of her name.

He and the other main speakers on Monday, liberal favorite U.S. Senator Elizabeth Warren and first lady Michelle Obama, offered stirring endorsements of Clinton as the party tried to push through the discord and find a common goal in beating Republican Donald Trump in the Nov. 8 election.

The furor in Philadelphia was a setback to Democrats' hopes that their convention would contrast with Trump's sometimes chaotic White House campaign and show the party moving beyond the bruising primary battle between Sanders, 74, a U.S. senator from Vermont, and former Secretary of State Clinton, 68.

Supporters see Clinton's Washington credentials - she has also been a first lady and a U.S. senator - as showing she has the experience needed for the White House. Detractors view her as too cozy with the establishment, and with political baggage dating back to the start of her husband's first term in 1993.

The convention's second day is aimed at highlighting Clinton's work on issues such as women, families and healthcare and as the country's top diplomat, a Clinton campaign official said.

It will include a prime-time speech by her husband, former President Bill Clinton, and the formalities of nominating Clinton to be the first woman U.S. president.

In a show-stealing speech on Monday night, Michelle Obama linked that landmark to her own husband's role as the first black U.S. president.

"I wake up every morning in a house that was built by slaves, and I watch my daughters, two beautiful and intelligent black young women, playing with their dogs on the White House lawn," Obama said.

"And because of Hillary Clinton, my daughters and all our sons and daughters now take for granted that a woman can be president of the United States."



'WE WANT BERNIE'

Sanders, who drew a fervent following of youth and liberals during a primary campaign that called for a tough hand on Wall Street and more aggressive steps to counter social inequality, struggled on Monday to get his own supporters in line.

At a meeting before the convention began, he was jeered by his own delegates when he urged them to back Clinton and focus on defeating Trump, a man he called a "bully and a demagogue." urn:newsml:reuters.com:*:nL1N1AB1VN

"We want Bernie!" they shouted in anger at both Clinton's victory in the race for the Democratic nomination and emails leaked on Friday suggesting the party leadership had tried to sabotage Sanders' insurgent campaign.

"Brothers and sisters, this is the real world that we live in," Sanders pleaded.

Trump reveled in the Democrats' opening day disorder, and made a pitch for Sanders voters to turn to him.

"Sad to watch Bernie Sanders abandon his revolution. We welcome all voters who want to fix our rigged system and bring back our jobs," Trump said on Twitter. Sanders had "totally sold out" to Clinton, he added in another tweet.

A Clinton campaign official noted on Tuesday that while Sanders had backed Clinton, the runner-up in the Republican primary contest, U.S. Senator Ted Cruz, refused to endorse Trump at his party's convention last week.

In the opening hours of the Democrats' gathering, party officials struggled to carry out business as angry Sanders supporters roared their disapproval, drawing a deafening response from Clinton delegates.

"We're all Democrats and we need to act like it," U.S. Representative Marcia Fudge of Ohio, the convention's chairwoman, shouted over the uproar.

Sanders tried to head off the disruptions, sending an email to delegates as the convention opened urging them not to interrupt the proceedings.

Several speakers pleaded for peace between the factions. Comedian Sarah Silverman, a Sanders supporter, said she would support Clinton "with gusto" and sternly added, "To the 'Bernie or Bust' people, you're being ridiculous."

Democratic National Committee Chairwoman Debbie Wasserman Schultz resigned, effective at the end of the convention, over the email controversy. At a gathering of Florida delegates on Monday, she was booed by Sanders supporters.

The DNC issued an apology on Monday to Sanders, his supporters, and the whole party for the email flap and said it would take action to ensure it never happens again.

Trump, a 70-year-old New York businessman who has never been elected to public office, was formally anointed as the Republicans' White House nominee last week.

He pulled ahead in at least one opinion poll on Monday, after lagging Clinton in most national surveys for months. A CNN/ORC opinion poll gave him a 48 percent to 45 percent lead over Clinton in a two-way presidential contest. (Additional reporting by Luciana Lopez; Writing by Frances Kerry; Editing by Jonathan Oatis) ((john.whitesides@thomsonreuters.com))