WASHINGTON (CNN) -- Sen. John McCain became the likely Republican nominee after Mitt Romney decided to suspend his campaign Thursday. Now, the Democrats are debating who would do better against the Arizona Republican.

Democrats are debating who would do better against Sen. John McCain, the GOP front-runner.

Two polls this month have asked registered voters nationwide how they would vote if the choice were between McCain and Democratic Sen. Hillary Clinton.

A CNN poll, conducted by the Opinion Research Corporation February 1-3, shows Clinton three points ahead of McCain, 50 percent to 47 percent. That's within the poll's margin of error of 3 percentage points, meaning that the race is statistically tied..

A Time magazine poll, conducted February 1-4, also shows a dead heat between Clinton and McCain. Each was backed by 46 percent of those polled.

Sen. Barack Obama believes he can do better, arguing "I've got appeal that goes beyond our party."

In the CNN poll, Obama leads McCain by 8 points, 52 percent to 44 percent. That's outside the margin of error, meaning that Obama has the lead.

And in the Time poll, Obama leads McCain by 7 points, 48 percent to 41 percent -- a lead also outside of the poll's margin of error of 3 percentage points.

In both polls, Obama looks stronger than Clinton. Why?

Obama's explanation: "I think there is no doubt that she has higher negatives than any of the remaining Democratic candidates. That's just a fact, and there are some who will not vote for her."

That was three weeks ago. Now, only two Democratic candidates remain.

Clinton does have higher negatives than Obama -- and McCain. Forty-four percent of the public say they don't like Clinton, compared with 36 percent who don't like McCain and 31 percent who don't like Obama, according to the CNN poll conducted February 1-3.

Why does Obama do better against McCain than Clinton? Obama does do a little better than Clinton with independents and Republicans.

But the big difference is men: Men give McCain an 18-point lead over Clinton, 57 percent to 39 percent, according to the CNN poll. The margin of error for that question was plus or minus 5 percentage points.

But if McCain and Obama went head to head, McCain's lead among men shrinks to three, 49 percent to 46 percent -- statistically a tie.

Women, on the other hand, vote for either Clinton or Obama by similar margins.

Some Democrats may be worried about how Obama will fare with white voters. Whites give McCain a 15-point lead over Clinton, (56 percent for McCain, 41 percent for Clinton).

But Obama actually fares better than Clinton with white voters. McCain still leads, but by a smaller margin, (52 to 43 percent).

Obama argues that he can reach across party lines. And he does do a little better than Clinton with Independents and Republicans, at least in these polls.

But the big difference is that Clinton doesn't draw very well with men. Obama does. E-mail to a friend

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