WASHINGTON (AP) Republican angst over the war in Iraq may be helping fuel John McCain's rise as a top presidential contender, even though he has been the campaign's highest profile supporter of the unpopular conflict, according to surveys in early voting states and interviews with GOP pollsters.

In states that have held GOP nominating contests so far, the Arizona senator has done better with people naming Iraq as the country's top problem than with those who picked other issues, entrance and exit polls of voters show. He has also done better with GOP voters saying they disapprove of the Iraq war than with those saying they approve.

Unlike Democrats and independents, most Republicans support the war, which several national polls show has been overtaken by the economy as the campaign's defining issue. Yet while only a minority of Republicans express displeasure with the conflict, their numbers are significant in the close race for the GOP nomination.

Republican pollsters say GOP voters unhappy over Iraq are generally displeased with how the Bush administration has conducted the conflict and don't oppose the war itself. They say that with violence in Iraq declining in recent months, those Republicans see it as vindication for McCain's longtime support for a continued strong U.S. military effort.

"He's been foremost among Republican critics of the tactics in Iraq, though stalwart about the importance of winning," said GOP pollster Whit Ayres, who is not affiliated with any presidential candidate. "He's getting votes from people who basically favor the war, as well as people who are critical of the effort we've made there."

Lance Tarrance, a pollster and informal adviser to McCain, said reduced U.S. and civilian casualties in Iraq are helping McCain get "the best of both worlds" support from Republicans who favor the war and from those who feel it has been mismanaged.

Others say the numbers showing McCain's strength among GOP war critics reflect that many of his supporters are independents or have moderate views on many issues, which happen to include doubts about the war, and are not driven by misgivings about the conflict.

"McCain's supporters are more moderate Republicans who are likelier to be less for the war," but whose support for him is based more on their overall ideology than on qualms about Iraq, said Tony Fabrizio, a Republican pollster not working for a candidate.

McCain's support is stronger among voters saying they disapprove of the war than among those who approve, according to polls of voters in the two early primary states where the war's popularity was measured.

He trailed Mitt Romney by 4 percentage points among voters in the New Hampshire primary who approve of the war but led him by 25 points with those disapproving. In Michigan, he trailed Romney by 15 points among those who approved but led by 7 points with war critics. Even when only looking at voters identifying themselves as Republican omitting independents, who tend to be more negative about the war those differences were the same or sharper.

Only about a quarter of voters in the Iowa and New Hampshire GOP contests cited Iraq as the country's chief problem, and a fifth or fewer said the same in Michigan, Nevada and South Carolina, the polls showed.

McCain did better with that group than he did with those naming something else as the top issue in each state but Nevada, where the numbers were too small to meaningfully compare. He finished first among those citing Iraq as the No. 1 problem in every state but Iowa, where he trailed overall Iowa winner Mike Huckabee.

Among early state voters calling themselves Republicans leaving out independents the differences were still clear.

McCain did 17 points better with Republicans calling Iraq the top issue than with those who didn't in Iowa; was about even in New Hampshire; 15 points better in Michigan; and 20 points better in South Carolina.