By Peter S. Canellos, Globe Staff
DENVER -- In a setting that was both portentous and a little pretentious, Senator Barack Obama tonight offered an acceptance speech that was grounded and targeted.
Obama took aim at presumptive Republican nominee John McCain with an unsmiling aggressiveness that seemed to surprise even his supporters.
"I've got news for you, John McCain," he said in one passage that was typical of his direct tone. "We all put our country first."
Gone was much of the soaring rhetoric of hope that defined his primary campaign; and while he alluded to his biracial, international life story and the historic nature of his candidacy, he mentioned them only obliquely. He let his diverse audience of devoted fans, crowded into a football stadium, make their own point about racial unity and togetherness.
The speech itself was mostly fighting words. He that declared McCain's plan to allow offshore drilling -- an effective issue for the Republican in a recent advertising campaign -- was no long-term solution to the energy crisis: "Not even close."
The toughness seemed to signal an awareness that Obama, who maintains only the narrowest of leads in the polls, had to make a stronger case against the Republicans. In recent weeks, as the novelty of Obama's candidacy wore off, it became clear that the urge for change in the country wasn't enough to carry him to victory.
"I think he knows he's going to have to fight this one out," said Dante Scala, a political scientist at the University of New Hampshire. "I think the change in tone is going to make a lot of Democrats happy."
The setting for Obama's speech -- a football stadium that fit more than 84,000 cheering fans -- was chosen before McCain's recent rise in the polls, and seemed designed to highlight the candidate's charisma and the enthusiasm of his supporters.
Up to now, such pageantry had been part of the point for Obama. It illustrated the core messages of the campaign: Diversity, grassroots empowerment, and charisma, with Obama serving as a kind of political evangelist preaching renewal.
But there has always been a yearning among Democrats for a firmer core to the Obama campaign, and a greater urgency. Tonight's speech sought to answer that yearning with specifics on his tax plan (which he says would reduce taxes on 95 percent of Americans), energy plan (eliminate dependence on Mideast oil in 10 years), and healthcare plan.
He also showed a willingness to challenge McCain on foreign policy -- accusing the Republican of going soft on Afghanistan while talking tough about Iraq.
"He went at McCain's strength," said Wayne Lesperance, a political scientist at New England College. "That says a lot about his confidence going forward."
The giant audience seemed to agree, sending Obama out of Denver with a burst of cheers. And the sheer vastness of the event, with its nearly five-hour program resembling a telethon, was impressive.
It wasn't all uplifting: Having Colorado's Democratic party leader Ray Rivera show up from time to time to shill for money while a big lighted sign broadcast Obama's web address probably struck some viewers as tacky; and the parade of "average" Americans sharing their economic grievances had an undignified consumer-helpline quality.
McCain, in a shrewd bit of counterprograming, ran a simple TV ad with only himself on the screen, congratulating Obama on "this historic day."
The ad showed a good sportsmanship that had been lacking in McCain's increasingly negative campaign and was mostly missing at tonight's Democratic extravaganza.
McCain's ad may also have contained a coded message, suggesting that the Republican intends to keep separating Obama's "historic" accomplishments -- and his status as a political celebrity -- from the hard issues of the campaign.
But Obama seems to have sussed him out on that one, and laid the groundwork for a fierce rebuttal.
"I don't know what kind of life John McCain thinks celebrities live, but this has been mine," Obama declared, after citing the hardships of his mother and grandparents -- including the little-known fact that his mother once received food stamps.
Obama left little unsaid tonight, and set the tone for a rugged general-election campaign to come.
About Political Intelligence
Glen Johnson is Politics Editor at boston.com and lead blogger for "Political Intelligence." He moved to Massachusetts in the fourth grade, and has covered local, state, and national politics for over 25 years. E-mail him at firstname.lastname@example.org. Follow him on Twitter @globeglen.