President Bush, his victory party delayed 12 hours instead of 36 days, as it was in 2000, claimed a broad mandate for his policies yesterday, declared "a duty to serve all Americans" and vowed to try again to become a uniter, not a divider.

The president's promise, coming after a presidential campaign that will be remembered for the blistering rhetoric and advertising of both candidates, echoed a declaration he made after the Florida recount battle of four years ago, when he said in the chamber of the Texas House of Representatives that he "was not elected to serve one party, but to serve one nation."

Yesterday's emotional celebration at the Ronald Reagan Building marked a triumphal ending to a roller-coaster week. Bush had looked sluggish in surveys before Election Day and was down sharply in exit polls taken while the polls were open, yet he won both the popular and the electoral votes -- racking up more of the former than any presidential candidate in history.

The party was a rare joint appearance for Bush and Vice President Cheney, and they were surrounded onstage by their families -- including Cheney's daughter Mary and her partner, Heather Poe, who had rarely appeared together during the campaign.

Karen Hughes, a longtime Bush aide, waved a flag as if it were her first rally. Bush introduced senior adviser Karl Rove as "the architect."

It was the second try at a celebration. With most revelers gone and others asleep on the Reagan Building's marble floors as dawn neared yesterday, Bush's plans to claim victory in the race were postponed after Sen. John F. Kerry (D-Mass.) declined to concede.

Bush spent election night watching returns in the family quarters of the White House, shuttling from sitting rooms filled with family and guests to a war room that Rove had built in the Old Family Dining Room.

Republican officials said Bush and some aides, seared by the experience of 2000, wanted to claim victory without waiting for Kerry to concede after the combined calls by various television networks gave them more than the required 270 electoral votes.

But others involved in the discussions pointed out that this time they were headed toward a clear win, and that no one could take it from them. In the view of those advisers, Bush could choose to be gracious. He wound up delaying his appearance from late morning to 3 p.m. to allow Kerry a chance to speak first.

White House officials said they had no contact with the Kerry campaign on election night, and Kerry's aides announced at 2:44 a.m. that they would have no further statements until morning.

Bush, who is usually in bed by 10 p.m. but stayed up until 5 a.m., had spent the night huddling with Rove and other members of his staff to try to determine when he could make a solid case that he had won 270 electoral votes. Rove and White House communications director Dan Bartlett angrily pushed television networks to declare Bush the winner. Some networks had called Ohio for him, and others said he had won Nevada. The combination of the two would put him over 270, but no network had declared Bush the winner.

So at 5:39 a.m., with only about 100 people left at the celebration, White House chief of staff Andrew H. Card Jr. went to the rostrum to declare that Bush "has won the state of Ohio" and that his "margin is statistically insurmountable."

But Card said the president "has decided to give Senator Kerry the respect of more time to reflect on the results of this election."

Kerry called Bush at 11:02 a.m. The president's aides said he took a seat at his Oval Office desk for the conversation, which lasted three or four minutes. According to the White House, Bush told Kerry: "I think you were an admirable, worthy opponent. You waged one tough campaign. I hope you are proud of the effort you put in. You should be." Bush told aides afterward that Kerry was "very gracious," aides said.

The Bush-Cheney campaign summoned supporters to the do-over celebration by e-mail.

"We had a long night, and a historic night," Bush said when he finally took the stage, which featured a backdrop that simulated a confetti shower. "Because we have done the hard work, we are entering a season of hope."

Bush vowed that in his second term, he will reach out to Democrats in pursuing an agenda of fighting terrorism, strengthening the economy, overhauling the tax code, adding private accounts to Social Security and upholding "our deepest values of family and faith."

"Reaching these goals will require the broad support of Americans," Bush told flag-waving staff members and supporters in the atrium of the Reagan Building. "So today I want to speak to every person who voted for my opponent: To make this nation stronger and better I will need your support, and I will work to earn it. I will do all I can do to deserve your trust. A new term is a new opportunity to reach out to the whole nation."

Between hardball politics with Capitol Hill and the divisive decision to invade Iraq, Bush never achieved his self-description from the 2000 campaign as a uniter, not a divider. On Monday, his last full day of campaigning, he attacked Kerry by name 39 times.

Bush said yesterday that he was humbled by the trust and confidence reflected in the returns. "With that trust comes a duty to serve all Americans," he said. "I will do my best to fulfill that duty every day as your president."

Bush concluded with a salute to the people of Texas, where he was twice elected governor. "We have known each other the longest, and you started me on this journey," he said. Then he took the hand of first lady Laura Bush, waved and disappeared into a tunnel covered with blue fabric, walking toward the second term that his father did not achieve.

President Bush takes the concession phone call from Sen. John F. Kerry. Daughters Jenna and Barbara Bush listen to the president's speech. Bush and first lady Laura Bush wave to supporters after the president delivered his victory speech. The celebration was delayed until after Sen. John F. Kerry (D-Mass.) called to concede.Cabinet and other administration officials applaud President Bush's arrival for a celebration of his victory. Passers-by pause to watch a monitor at Rockefeller Plaza in New York showing the president's victory speech.