Mitt Romney seems firmly in command in a Republican presidential field that hasn't figured out how to stop him.
Twelve weeks before the first party voting, the GOP establishment is coalescing around the former Massachusetts governor. He has more campaign experience, money and organization than anyone else. He showed again this week that he's the best debater in the bunch. And President Barack Obama's campaign is treating him almost as the presumptive nominee _ even though Romney still faces challenges in some early voting states.
The biggest question in Republican circles is when and how Texas Gov. Rick Perry will use his own substantial campaign funds to buy TV ads hitting Romney's record on health care, abortion, gay rights and job creation.
Perry's campaign, which seems best-positioned to challenge Romney, dropped broad hints Wednesday that the moment is near.
"Now that the field is full, the air war will start soon," said Katon Dawson, former chairman of the South Carolina GOP and Perry's top adviser in the state. "We seem to be inside a 100-day window," Dawson said. "Governor Perry will be extremely competitive on the air."
The tone is different up the coast in New Hampshire. Among rank-and-file Republicans there, even those who favor other candidates have a sense that Romney has gained an air of inevitability. "It's very frustrating," said state Rep. Jim Waddell, of Hampton, who backs former Utah Gov. Jon Huntsman.
Some go even further about Perry's recent drop. "In New Hampshire, he certainly is done," said GOP state Rep. Keith Murphy, who is uncommitted in the race.
Perry's advisers say there's plenty of time to overtake Romney in key states. They are frustrated by bad reviews of the Texan's debate performances, including Tuesday's in New Hampshire. They say it's Romney who is ripe for sharp criticism of his revised positions on abortion, gay rights and gun control, all now markedly more conservative than in the 1990s and early 2000s.
In the debates so far, Perry has generally fallen flat when hitting Romney's "flip-flops" and the health care initiative that required Massachusetts residents to obtain medical insurance. Perry's advisers say aggressive TV ads will do a far more powerful job.
Although Republican and Democratic insiders see Romney as the front-runner, several signs give Perry and the other rivals hope. Most Republican polls show Romney falling well short of a majority of support, as restless voters consider one alternative after another.
Rep. Michele Bachmann of Minnesota surged in mid-summer, then fell as Perry briefly soared. In recent polls, former pizza company executive Herman Cain has ranked as Romney's top rival, although few campaign strategists believe he will be the nominee.
An NBC-Marist College poll in Iowa found that tea party supporters prefer Cain. In national polls, combined support for Cain, Perry and Bachmann exceeds Romney's support.
A Wall Street Journal/NBC News poll of Republican primary voters released Wednesday found Romney and Cain in a dead heat, while Perry dropped to 16 percent. Cain was the first choice of 27 percent of those surveyed, while Romney held firm at 23 percent. The poll had a margin of error of 5.35 percent. The poll was taken Oct. 6-10.
National polls matter less than surveys closer to home in a handful of early voting states, including Iowa, New Hampshire and South Carolina. Many campaign strategists say Perry must win the Iowa caucus, or at least far outdistance Romney there, to survive the New Hampshire primary, where Romney is favored.
The next states to vote will be Nevada, where Romney seems strong, and South Carolina, where Perry hopes evangelical Christians will back him.
The issue of Romney's Mormonism flared at a conservative gathering in Washington last week, and it might be a factor in South Carolina.
Bob Jones III, chancellor of Bob Jones University, told the Greenville News he's undecided on whether he'll endorse anyone. "There's a vast chasm between what a Mormon believes and what a Christian believes," Jones said. He added, however, "We're really electing a president, not a preacher."
In Iowa, Romney continues an under-the-radar strategy designed to keep expectations low while positioning himself for a possible late surge. Four years ago Romney poured huge sums of money and time into the state, then suffered a crushing loss to Mike Huckabee.
Romney has visited Iowa only twice this year, but he is gradually ramping up his public schedule there. His small but growing staff stays in close touch with his 2008 supporters, and Romney is reaching out to business owners, agriculture workers and the elderly.
Romney seems eager for several of the more conservative candidates to remain viable, to pull support from Perry and possibly open a path for a Romney victory in Iowa with a modest plurality. In Tuesday's debate, when given a chance to ask anyone a question, Romney lobbed a softball to Bachmann, a tea party favorite.
"You've laid out some pretty bold ideas," Romney said, asking about her anti-spending and anti-regulation agenda.
Kevin Meetze of Irmo, S.C., is typical of GOP voters who see Romney as best able to beat Obama.
"I think he's got what to me appear to be practical ideas to address a lot of the issues that we face, particularly financially and in regard with all these other countries that we're having struggles with," said Meetze, who owns a plumbing business.
In a sign of Romney's strength, Obama's chief political adviser, David Axelrod, held a conference call with reporters Wednesday aimed solely at the former Massachusetts governor. In a preview of the flip-flop charges that Perry might raise in TV ads, Axelrod said Romney had shifted his stances on taxes, health care and trade with China.
"If you are willing to change positions on fundamental issues of principle, how can we know what you will do as president?" Axelrod said.
Romney says his changes in positions are based on a genuine evolution of his thoughts, not on political expediency.
One possible reason that second-tier candidates such as Rep. Ron Paul, former Sen. Rick Santorum and former House Speaker Newt Gingrich remain in the race is a widespread belief among many GOP voters that Obama is doomed to defeat, so they might as well nominate the candidate they really want.
"I could vote for the pizza guy," Steve Koontz, a 59-year-old retired pilot in Las Vegas, said of Cain. But he's more likely to vote for Paul, as he did in 2008, he said.
"A lot of people that are like me will never vote for Romney," Koontz said. "He is the establishment. He is Romneycare in Massachusetts."
Koontz said he's not worried about the primary's outcome. "Anybody can beat Obama," he said.
Associated Press writers Tom Beaumont in Iowa, Steve Peoples in New Hampshire, Cristina Silva in Nevada and Jim Davenport in South Carolina contributed to this report.