Intensity may help the Republican

John McCain last night put Barack Obama through a red-hot grilling, barely hiding his disdain for the Illinois senator and his outrage over Obama's policies.

Obama responded with cool, collected answers - sometimes too cool, answering McCain's teeth-gritting attacks with a grin that seemed more amused than offended.

The difference in the senators' temperatures - a combination of long-evident personality differences and McCain's increasing sense of urgency about Obama's growing lead in the polls - probably struck different voters in different ways.

But McCain's very intensity may have at least prompted some voters to take a second look at Obama and his policies.

"McCain came out swinging," said Wayne Lesperance, political scientist at New England College in Henniker, N.H. "Barack Obama was very cognizant of his lead and very cautious. It was reminiscent of the last round of a fight where a boxer is just trying not to be hit. If you score it on points, McCain won, but not by nearly enough to overcome Obama's lead."

McCain sought to sow doubts about Obama in many ways, some of which seemed likelier to stick than others. They included Obama's truthfulness - "There's the eloquence," he chimed at one point, claiming Obama's support for restrictions on late-term abortions had a hidden loophole in providing exceptions for "the health of the mother." (It's a loophole, but one that's been crucial to past Supreme Court decisions and hardly hidden.)

McCain also questioned Obama's judgment ("You don't tell other countries you're going to unilaterally renegotiate," he declared about Obama's vow to reopen the North American Free Trade Agreement) and personal associations, sounding like a prosecutor demanding all the facts about any links between Obama's campaign and the liberal activist group ACORN, which has been accused of voter registration fraud. (There are no links, Obama said.)

While McCain often undermined his points with overstatements - claiming, for example, that ACORN's alleged offense was "destroying the fabric of democracy" - his clear-eyed anger at Obama was striking enough to make Obama's coolness seem overly lax.

McCain also scored substantively by focusing on "Joe the plumber," a real person who wants to buy his business and worries that Obama's tax policies would hurt him.

Obama pointed out that Joe would have to earn more than $250,000 a year to see his taxes go up, and that Joe might have benefited from Obama's plan during the many years he earned less.

But viewers probably were numb to the distinction: They're more likely to remember that an average Joe was worried that Obama would take his money. And McCain hammered home his point by accusing Obama of class warfare and returning to Joe later in the debate to suggest he could suffer under Obama's healthcare plan, as well.

The exchange over Joe did more than put a human focus on McCain's criticisms - it allowed McCain to take the offensive on the tax issue. In their first two debates, Obama had all but taken the tax issue away from McCain, stressing his own plans to cut taxes for 95 percent of taxpayers and portraying McCain's plan as a giveaway to the rich.

McCain's performance wasn't friendly or gracious; but it may have been effective.