Barack Obama, whose campaign theme is "change we can believe in," promised Thursday to "spell out exactly what that change would mean."

But instead of dwelling on specifics, he laced the crowning speech of his long campaign with the type of rhetorical flourishes that Republicans mock and the attacks on John McCain that Democrats cheer. The country saw a candidate confident in his existing campaign formula: tie McCain tightly to President Bush, and remind voters why they are unhappy with the incumbent.

Of course, no candidate can outline every initiative in a 44-minute speech _ especially one that also must inspire voters, acknowledge key friends, and toss in some autobiography for the newly-interested. And Obama did touch on nitty-gritty subjects, such as the capital gains tax and biofuel investments.

He said he would "find ways to safely harness nuclear power," a somewhat more receptive phrase than he typically uses for that subject.

But most of his address echoed and amplified the theme that dominated the four-day Democratic nominating convention here: George Bush.

"John McCain has voted with George Bush 90 percent of the time," Obama said. "I'm not ready to take a 10 percent chance on change."

Some of his comments about McCain were unusually sharp. "I've got news for you, John McCain," Obama said, defying anyone to challenge his patriotism. "We all put our country first."

Obama, whose grin can light up an auditorium, was earnest and unsmiling throughout most of the speech, particularly when skewering his opponent. "John McCain stands alone in his stubborn refusal to end a misguided war" in Iraq, he said sternly.

Obama's aides have long complained that he gets too little credit for including detailed proposals in his stump speeches, because listeners seem to remember only his stage presence and lofty rhetoric. Obama, who earlier had promised a "workmanlike" speech in Denver, seemed to acknowledge the problem, saying he would fill in the blanks.

Mostly, however, he touched on major issues quickly and lightly. It's an approach that may intrigue and satisfy millions of viewers just starting to tune in to the campaign seriously. The crowd at Invesco Field cheered deliriously, but Republicans almost surely will decry the lack of specifics.

For instance, Obama said it's time "to protect Social Security for future generations." But he didn't mention his main proposal, which is to add a new Social Security payroll tax to incomes above $250,000 a year.

He said he would "cut taxes for 95 percent of all working families," but did not say how.

He briefly mentioned abortion, gun rights, gay rights and other hot-button issues without delving into their sticky details. "Passions fly on immigration," Obama said, "but I don't know anyone who benefits when a mother is separated from her infant child or an employer undercuts American wages by hiring illegal workers."

On a few topics, he was a bit more specific. "I will eliminate capital gains taxes for the small businesses and the start-ups that will create the high-wage, high-tech jobs of tomorrow," he said.

Even if Obama had talked for three hours, of course, he could not have detailed enough proposals to quiet all his critics. But that's not the strategy.

Allies such as Arizona Gov. Janet Napolitano will doubtlessly defend his approach. A few hours before the speech, she said: "What he should not do is what he will be criticized for not doing: Give a detailed policy speech. This is not the place for that."

She said Republicans will criticize him no matter what. They will argue that his lofty speeches lack substance and details, she said, and a detailed speech that scrimps on soaring rhetoric will prove "he has lost his gift."

"They will try to Catch-22 his speech," Napolitano said.

Obama seemed to say, Bring it on, we're sticking to our theme: McCain equals Bush.

Editor's Note: Charles Babington covers politics for the Associated Press.

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