MADISON, Wis. (AP) — Barack Obama won Wisconsin's Democratic presidential primary Tuesday over rival Hillary Rodham Clinton, keeping the momentum heading into pivotal contests two weeks away and delivering another setback to the New York senator's campaign.

Republican Sen. John McCain soundly beat back a spirited effort from long-shot candidate Mike Huckabee to win the Wisconsin Republican primary.

The Associated Press made its calls based on surveys of voters as they left the polls and early results.

Obama, a senator from neighboring Illinois, had a modest lead among whites and was splitting the women's vote with his rival, according to the exit surveys conducted for the AP and television networks.

He also performed well with men and younger voters, middle-aged people and moderates while expanding his decisive leads with independents, college-educated, high income and very liberal voters.

Clinton appeared to look ahead to key primaries in Ohio and Texas on March 4, as she spent much of last week campaigning there before turning her attention to Wisconsin on Saturday. She spoke in Youngstown, Ohio, after her defeat in Wisconsin.

The exit poll data showed Clinton's most pivotal backers were lukewarm in their support. Women split their votes almost evenly between Clinton and Obama, and about six in 10 men favored Obama.

Don Haney of Wausau, a 68-year-old retired software developer and registered Republican, said he voted for Obama.

"He excites me," Haney said. "It's time for a change. From Hillary, I am hearing the past. From Obama, I am hearing the possibility of the future, with the recognition that campaigns are much different than being in office."

Huckabee campaigned hard in the state despite McCain's virtual lock on the party's nomination, hoping voters would "shock the world" and hand him a win. It wasn't to be.

Given that Wisconsin is traditionally a more moderate state, McCain's win wasn't a surprise. Anything less would have fueled talk that he does not have the full support of Republican Party faithful.

Wisconsin Republican Party Chairman Reince Priebus said McCain is an attractive candidate for the state's Republicans.

"I think he's got kind of the perfect combination of being a conservative, being a person who runs against the grain, who's a maverick, and seen as an independent which in this state works magically with the voters," Priebus said.

McCain had a commanding lead among women voters and voters over 45, and he held a 2-to-1 advantage among Catholics, while Huckabee again did well with born-again or evangelical Christians and voters who oppose abortion in all cases.

The exit poll figures came from partial samples of an exit poll conducted by Edison Media Research and Mitofsky International in 35 Wisconsin precincts for the AP and television networks.

Those interviewed included 878 Democrats, with a 5 percent margin of error, and 454 Republicans, with a 7 percentage point error margin.

In addition to Wisconsin's primary, Obama's native Hawaii was holding a Democratic caucus on Tuesday. Washington state was holding a relatively meaningless primary in which only half of the Republican delegates and no Democratic ones were being awarded.

Despite bitterly cold temperatures in the single digits across Wisconsin, turnout was predicted to be 35 percent, which would be the highest in 20 years for a presidential primary. Wisconsin's primary is open, meaning voters don't have to designate a party affiliation and they can register on election day.