New York, July 30 : Some Republicans are reportedly worried that presumptive presidential nominee John McCain may be going negative too early against potential Democratic rival Barack Obama.

They believe that 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.

According to the New York Times, they also believe that the drumbeat of attacks could also undermine his argument that he will champion a new brand of politics.

The paper quoted Todd Harris, a Republican strategist who worked for Mr. McCain in 2000, as saying that the present campaign was being pulled in two different directions -- “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 says that Obama has been taking shots at 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 McCain, says: “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.”

Some of his lines of attack have been accused of being misleading. McCain, for instance, said Obama had voted in the Senate “for tax hikes that would have impacted those making 32,000 dollars 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.

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 Obama and 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 McCain, by trying to make the election a referendum on Mr. Obama, risks ceding control of some of the narrative by constantly reacting.

“I think the campaign does have to be careful about its tone. A pure attack tone could be perilous,” said Mike Murphy, another former McCain aide. (ANI)