DENVER – For one evening, their political world was perfect. Or so it seemed.

Standing before thousands of delegates, almost half of them her backers, Sen. Hillary Rodham Clinton declared it time “to unite as a single party with a single purpose” and urged her followers to help elect once-bitter rival Barack Obama. “We are on the same team,” she said, after allowing the applause to build to a crescendo and linger, longer than usual – much like the Democratic primary race itself.

“Barack Obama is my candidate,” she said. “And he must be our president.”

But did she mean it? And would it matter?

True, her challenges Tuesday night were impossibly high, perhaps mutually exclusive.

She had to both promote her political future and unify her party. Clinton had to somehow convince people that she honestly thought Obama was ready for the presidency. But something stood in her way: Her words.

 Dec. 3, 2007: “So you decide which makes more sense: Entrust our country to someone who is ready on Day One ... or to put America in the hands of someone with little national or international experience, who started running for president the day he arrived in the U.S. Senate.”

 March 2008. “I know Sen. McCain has a lifetime of experience that he will bring to the White House. And Sen. Obama has a speech he gave in 2002.”

 Feb. 23, 2008: “Now, I could stand up here and say, 'Let's just get everybody together. Let's get unified.' The skies will open, the light will come down, celestial choirs will be singing and everyone will know we should do the right thing and the world will be perfect.”

There in no such thing as a perfect world, though the Clinton and Obama image teams tried their best to create one. Hundreds of “Hillary” signs danced before the TV cameras, bearing her breezy blue signature. Her misty-eyed husband, former President Clinton, watched from above.

By the time she was done, Sen. Clinton had delivered a strong, convincing affirmation of Obama and, just as importantly, a thumping of McCain. She did her part. Her husband takes the stage Wednesday and then Obama must make his case to the American people that he will be ready on Day One.

That there's more to him than a single speech.

That he's the perfect man for troubled times. She brought the party together, for one night anyway, and now it's up to Obama to close the deal with voters.

Unlike Obama, she no longer needs to worry about her favorability ratings so there was no pulling punches.

“No way,” Clinton said. “No how. No McCain.”

She said McCain would be an extension of the Bush administration. No jobs. Poor health care coverage. High gas prices. Home foreclosures. “More war,” she said, “Less diplomacy. More of a government where the privileged comes first, and everyone else come last.”

In other words, Clinton seemed to say, even if Obama is everything she said during the campaign, he's still a better candidate than McCain. The speech was as much of an attack on McCain as it was an embrace of Obama. “We don't need four more years of the last eight years,” she said.

The crowd, Obama and Clinton delegates alike, loved it.

She took the high road Tuesday night because it was also her best road politically; if Obama wins, she still emerges as a central voice in American liberalism, replacing the ailing Sen. Edward Kennedy. And if Obama loses, as Hillary said he would during the campaign, she is blameless and the party can turn back to her without guilt in four years.

Behind the scenes Tuesday, the Obama and Clinton camps struck a tentative deal that would allow some states to cast votes in a roll call before somebody – possibly Clinton herself – cuts short the tally and asks the convention to nominate Obama by unanimous consent. This was her price for ending her historic bid for the presidency in a manner that, however messy, still left Obama in a stronger position than Kennedy left Jimmy Carter in 1980, when the Massachusetts senator extracted platform concessions and shrank from the traditional unity show at the final gavel.

But she did extract her price.

The bill came due Tuesday. The crowd. The applause. The promise of a vote Wednesday, and a speech laced 17 times by some variation of the pronoun “I.”

“You never gave up,” Clinton told her delegates, a phrase that so perfectly fits her. “You never gave up. And together we made history.”

EDITOR'S NOTE: Ron Fournier has covered politics for The Associated Press for nearly 20 years.