Washington ? If Democrats want their best shot at defeating John McCain this fall, a new poll suggests Barack Obama may be a better bet than Hillary Rodham Clinton.

In an early look at how people view the presidential race after the Super Tuesday contests, Obama had a narrow 48 percent to 42 percent edge when pitted against McCain, the Republican Arizona senator, according to an Associated Press-Ipsos poll released Monday. Clinton was essentially tied with McCain, getting 46 percent to his 45 percent.

Even as Clinton and Obama continue their battle over their party’s nomination – a fight that may take weeks or months to resolve – the poll showed Obama doing better than his rival against McCain among some pivotal voters. These include men, minorities and moderates.

At the same time, Clinton did no better than Obama when pitted against McCain among two groups that have supported her in Democratic primaries so far: women and whites.

“We bring in voters who haven’t given Democrats a chance” in the past, said Obama pollster Cornell Belcher, citing the Illinois senator’s support from independents and other groups.

Mark Penn, Clinton’s chief strategist, spoke of her backing from women and Hispanics and said, “Hillary Clinton has a coalition of voters well-suited to winning the general election.”

McCain is the heavy favorite to win the GOP nomination following his strong showing in last Tuesday’s coast-to-coast voting and Mitt Romney’s decision to suspend his campaign. The AP-Ipsos poll shows, however, that the general election – still nine months off – looms as a difficult fight for him.

One reason McCain holds his own against Clinton is his support from men, who prefer him to the New York senator by 9 percentage points. That compensates for her 11-point advantage among women.

Obama does better than Clinton with men when paired against McCain, splitting the male vote with the Arizona senator. Obama does especially well with men under 45: He defeats McCain by 9 points among younger men, while McCain defeats Clinton with those voters by 7 points.

Meanwhile, Obama’s advantage over McCain among women is about the same as Clinton’s, blunting her edge in a group that has been the core of her strength in her fight for the Democratic nomination.