Des Moines, Iowa ? Mike Huckabee says John McCain is a hero. McCain says Huckabee is a good man. And they both seem to agree on this: Mitt Romney is neither.

The Republican rivals joined Sunday to criticize Romney – McCain in New Hampshire called him a waffler and Huckabee in Iowa questioned whether he can be trusted with the presidency, a sign of Romney’s strength in both states.

Romney’s camp accused the hard-charging Huckabee of “testiness and irritability,” a reflection of the brass-knuckles phase of the most open presidential race in half a century. Much is at stake: Iowa kicks off the election process Thursday with Democratic and Republican caucuses.

“Whoever wins Iowa could be the next president of the United States,” said Democratic consultant Stephanie Cutter, adding that a compressed election schedule may put a premium on momentum this year “and Iowa can be a rocket booster.”

New Hampshire votes just five days after Iowa.

The dynamics aren’t quite the same on the Republican side, but GOP consultant Scott Reed said Iowa “is going to make or break three-quarters of all the candidates.”

Polls show Democrats Hillary Rodham Clinton, Barack Obama and John Edwards tied for the lead in Iowa. Clinton and Obama are closely bunched in New Hampshire, too, where voters are often influenced by the results in Iowa.

The Democratic winner here will be hard to stop, especially if it’s a well-funded Clinton or Obama.

A new poll of the Republican race in Iowa suggested that Huckabee’s surprise surge in Iowa may have stalled – his lead over Romney evaporated. A victory here for Romney would send the former Massachusetts governor to his neighboring New Hampshire with a head of steam.

That explains why Huckabee, strongest in Iowa, and McCain, winner of the 2000 GOP primary in New Hampshire, both criticized Romney.

Huckabee said he may have been hurt by Romney ads and mailings criticizing his record as governor of Arkansas. He accused Romney of running a “very desperate and, frankly, a dishonest campaign.”

Romney has been less than candid about his record and campaign plans, a fact seized upon by Huckabee.

“If you aren’t being honest in obtaining a job,” Huckabee said, “can we trust you to be honest if you get the job?”

Huckabee defended McCain against negative ads by Romney. “I felt like that when Mitt Romney went after the integrity of John McCain, he stepped across a line,” Huckabee told NBC. “John McCain’s a hero in this country. He’s a hero to me.”

Huckabee scrapped a public appearance at an Iowa church, his only open event of the day, in favor of attending a private service and taping new ads – perhaps to counter Romney’s.

United by a common foe, McCain spoke up for Huckabee. “Look, I’m flattered that (Romney) would be attacking me. He’s attacking Huckabee in Iowa, who’s a good man. And it shows that they’re worried,” McCain said.