Branstad is the latest Romney supporter to cite “momentum” in his endorsement and to urge the party to unite behind the front-runner as the nominee. “I think it’s time that we focus on the general election,” Branstad said.

Branstad stayed neutral through the Iowa caucuses in January. His state was the first to vote in the Republican contest. However, Branstad was very vocal in January in his criticism of Romney’s initial strategy to avoid campaigning in Iowa.

Romney invested heavily in the state during his first run, in 2008, and suffered a disappointing loss. This year, Romney skipped the Ames straw poll and spent very little time and money in the state ahead of the January vote. Branstad said at the time that Romney was making a “big mistake” by not spending more time in Iowa. When the vote ended up being a virtual tie between Romney and Rick Santorum, Branstad said it should teach Romney a lesson.

Branstad said that he has “great respect” for all of the candidates. He particularly singled out Santorum, Romney’s nearest rival. “I have the greatest respect for Sen. Santorum and the fact that he did as I suggested and visited all 99 counties [while campaigning in Iowa],” he said.

“I’m proud of the fact that the people who came in 1, 2, 3, 4 are the ones who are still in the race,” he said. “We’ve never said that Iowa picks the winner necessarily.”

Branstad said he has not discussed hitting the campaign trail to stump for Romney with the campaign.