Merrimack, N.H. ? Republican presidential candidate Sam Brownback on Tuesday criticized President Bush and two GOP rivals, saying the presidency isn’t a foreign policy classroom.

Brownback’s criticism that governors often do not have the foreign policy experience necessary to be president was aimed primarily at rivals Mitt Romney and Mike Huckabee, both former governors. But in the process, he also took a jab at the man they all seek to replace, former Texas Gov. George W. Bush.

“We’ve got to walk more humbly and a lot more wisely than the current president,” said Brownback, a Kansas senator and former member of the Senate Foreign Relations Committee.

“I really believe this next president needs to go in with knowledge on foreign policy and not learn it on the job,” said Brownback, who has been a vocal activist against the genocide in Darfur.

“We have a tendency to elect governors as president because people like executive experience. I don’t have any problem with that. The problem is most governors don’t have foreign policy experience.”

Brownback finished third in the Iowa straw poll last weekend. Romney, the former Massachusetts governor, easily won the contest and Huckabee, the former Arkansas governor, finished a distant second.

Brownback’s criticism of Bush might help him in New Hampshire, where the unpopular war in Iraq was an important factor in the defeat of two incumbent GOP congressmen in 2006.

Brownback has scuffled with Romney in recent weeks over social and political policy, including fiercely criticizing Romney’s changed position on abortion. Again on Tuesday he told New Hampshire’s WKXL-FM that Romney “hasn’t been consistent on these positions in the past. He’s stated that himself. He continues really even to support new research on the youngest of humans.”

Romney retorted during a recent debate: “I get tired of people that are holier than thou because they’ve been pro-life longer than I have.”

Brownback, who spoke at Thomas More College, also said he now will try to match his performance in Iowa, where social conservatives hold sway, in New Hampshire.

“We’re building a grassroots campaign. I am not an overly funded candidate,” he said after his campaign breakfast.