SPARKS, Nev. — In recent days Senator John McCain has charged that Senator Barack Obama “would rather lose a war in order to win a political campaign,” tarred him as “Dr. No” on energy policy and run advertisements calling him responsible for high gas prices.
The old happy warrior side of Mr. McCain has been eclipsed a bit lately by a much more aggressive, and more negative, Mr. McCain who hammers Mr. Obama repeatedly on policy differences, experience and trustworthiness.
By doing so, Mr. McCain is clearly trying to sow doubts about his younger opponent, and bring him down a peg or two. But some Republicans worry that by going negative so early, and initiating so many of the attacks himself rather than leaving them to others, Mr. McCain risks coming across as angry or partisan in a way that could turn off some independents who have been attracted by his calls for respectful campaigning.
The drumbeat of attacks could also undermine his argument that he will champion a new brand of politics.
“The McCain campaign, I think, is being pulled in two directions,” said Todd Harris, a Republican strategist who worked for Mr. McCain in 2000. “On the one hand, this race is largely a referendum on Obama, and whether or not he’s going to pass the leadership threshold in the eyes of voters. So being aggressive against Obama on questions of leadership and trust and risk are important, but at the same time I think they need to be very careful because McCain is not at his best when he is being overly partisan and negative.”
The McCain campaign said that Mr. Obama had been taking shots at Mr. McCain for some time, and that Mr. McCain was simply trying to draw the contrast between the two candidates.
Mark Salter, a senior adviser to Mr. McCain, noted that the two candidates addressed the same Hispanic groups three times this summer, and that at the first two appearances Mr. McCain declined to criticize Mr. Obama, only to be criticized. (“He suggested in his speeches here and there that I turned my back on comprehensive reform out of political necessity,” Mr. McCain complained.) The third time, he said, before La Raza, Mr. McCain decided to “correct the record.”
“There are no cheap shots,” Mr. Salter said. “There are honest differences between them. They want to take the country in different directions, and we’ll talk about it.”
Mr. McCain drew contrast after contrast with Mr. Obama at a town-hall-style meeting in a high school gym here on Tuesday, though he took a more-in-sorrow-than-in-anger tone.
“Senator Obama is an impressive speaker,” he said. “And the beauty of his words has attracted many people, especially among the young, to his campaign. I applaud his talent and his success. All Americans, all Americans should be proud of his accomplishment. I know I am.
“My concern with Senator Obama is on big issues, and small issues, what he says and what he does are often two different things. And that he doesn’t seem to understand that the policies he offers would make our problems harder, not easier to solve.”
Mr. McCain went on to criticize Mr. Obama for seeking pork-barrel spending (“nearly a million dollars for every working day he’s been in office”), accused him of wanting to raise taxes, painted him as an obstructionist on energy policy, rapped him for abandoning his pledge to take public financing, and criticized his Iraq policy.
Some of his lines of attack have been accused of being misleading. Mr. McCain, for instance, said Mr. Obama had voted in the Senate “for tax hikes that would have impacted those making $32,000 a year.” FactCheck.org, a nonpartisan Web site, said the vote was on a budget resolution to raise taxes on people making $41,500 a year; the $32,000 figure, it said, was the amount of taxable income those people had.
An advertisement criticized Mr. Obama for the high price of gas. “Who can you thank for rising prices at the pump?” an announcer intoned, as chants of “Obama, Obama” were heard.
Dan Schnur, who worked on Mr. McCain’s 2000 campaign and is the director of the Jesse M. Unruh Institute of Politics at the University of Southern California, said the McCain campaign seemed to be drawing on lessons from watching the Democratic primary fight between Mr. Obama and Senator Hillary Rodham Clinton.
“It wasn’t until the last weeks of the primary that Clinton and her campaign really took the gloves off on Obama, and as it happens it was too little, too late,” he said. “Obama is at his best when he talks from the mountaintop, and Clinton showed that the best hope for an opponent is to pull him back down to earth. McCain’s campaign quickly decided not to wait as long as she did.”
But some Republicans say privately that Mr. McCain, by trying to make the election a referendum on Mr. Obama, risks ceding control of some of the narrative by constantly reacting.
Mike Murphy, a Republican media consultant who worked on Mr. McCain’s 2000 campaign, said that while the campaign needed to balance positive messages about Mr. McCain with negative ones about Mr. Obama, he thought it should ultimately be more about what Mr. McCain would do than Mr. Obama.
“I think the campaign does have to be careful about its tone,” Mr. Murphy said. “A pure attack tone could be perilous.”