DENVER — Hillary Rodham Clinton, accepting defeat with grace and generosity, moved to close the divide among fellow Democrats on Tuesday night by offering a forceful and unequivocal endorsement of her fierce rival, Barack Obama.
"Barack Obama is my candidate," she said to a thunderous roar from Democratic convention delegates, whose allegiance was split nearly evenly during a long and contentious primary season. "And he must be our president."
In a speech anticipated for weeks, ever since her historic bid for the White House fell agonizingly shy, Clinton urged her supporters to value party over pettiness and join her in making the Illinois senator's cause their own.
"Whether you voted for me, or voted for Barack, the time is now to unite as a single party with a single purpose," Clinton said, as delegates waved signs reading "Hillary" on one side and "Unity" on the other.
"We are on the same team," Clinton said, "and none of us can sit on the sidelines."
She offered the briefest of kind words for Republican Sen. John McCain of Arizona, a personal friend but also Obama's foe in the fall campaign. "He has served our country with honor and courage," Clinton said. But she quickly added, "We don't need four more years of the last eight years."
The appearance capped a day again dominated by the dynastic intrigue surrounding the New York senator; her husband, former President Bill Clinton; and their grudging eclipse by Obama and his supporters.
It came as the message emanating from the Denver convention hall abruptly pivoted from biography to an emphasis on the differences between Obama and McCain. "If he's the answer," New York Gov. David Paterson taunted from the stage, "then the question must be ridiculous."
The shift came after some Democrats griped about Monday's feel-good program, intended to leaven Obama's lofty image with glimpses of the candidate as family man. By contrast, one speaker after another took turns on Tuesday pummeling the Arizona senator -- and President Bush -- using economic issues as their club.
The theme was summed up by the red-and-white signs that delegates waved at one point: "McCain," they read. "More of the Same."
"Do we want four more years of Bush-McCain, or do we want the change we need?" asked Rep. Rahm Emanuel, who straddles the two poles of the Democratic Party as a former aide to President Clinton and a congressman from Obama's hometown of Chicago.
"There is only one candidate from the middle class . . . that understands the middle class," Emanuel said. "George Bush has put the middle class in a hole, and John McCain has a plan to keep digging that hole with George Bush's shovel."
Obama pressed the point at a campaign stop in Kansas City, Mo. Stumping inside an airline maintenance hangar -- where he was introduced as "a true working man's president" -- Obama called McCain "out of touch" on the economy and offered this mocking proposition: "If you think the last eight years have been good, you need to vote for John McCain."
His running mate, Sen. Joe Biden of Delaware, chimed in as well. Speaking at a convention round-table on the economy, Biden ripped McCain's plan to extend the Bush tax cuts for well-off Americans. How, he demanded, can Republicans call themselves a party "that values people?"
Proving to be one of the night's biggest hits, a rollicking Montana Gov. Brian Schweitzer called McCain beholden to Big Oil and mocked the senator's calls to increase domestic oil drilling, along with his admission that he was not sure how many houses he owned. "We can't simply drill our way to energy independence if you drilled everywhere -- if you drilled in all of John McCain's backyards, even the ones he doesn't know he has," Schweitzer said.
In the night's keynote address, former Virginia Gov. Mark R. Warner nudged McCain in softer terms, echoing Obama's 2004 convention call for unity to address the nation's ailments. "This election is not about liberal versus conservative," Warner said in a workmanlike address greeted with courteous but tepid applause. "It's not about left versus right. It's about the future versus the past."
Clinton's 26-minute speech presented a nostalgic tour of her so-close run for the White House, no less dramatic than Obama's bid to become the nation's first black president. She cited the reasons she ran for president, including universal healthcare, clean energy and an end to the Iraq war. Above all, she said, was standing up for Americans who are "invisible" to their government.
"Were you in this campaign just for me?" she asked. "Or were you in it for that young Marine and others like him? Were you in it for that mom struggling with cancer while raising her kids? Were you in it for that boy and his mom surviving on the minimum wage? Were you in it for all the people in this country who feel invisible?"