In an e-mail message sent Wednesday evening to supporters, surging GOP presidential candidate Newt Gingrich pledged not to attack his rivals for the primary nod in TV advertisements, calling them instead “friends.”

“There will be no 30-second attack ads against my friends who are also seeking the Republican nomination. I will focus my criticism on President Obama,” Gingrich vowed.

The e-mail comes after a brief exchange in which Mitt Romney, his biggest competition for the GOP nod, slammed Gingrich yesterday for being a “lifelong politician.” Gingrich hit back that Romney was the “former frontrunner.”

Gingrich, who seems to be the most likely vessel for anti-Romney sentiment in the GOP presidential race at this point, weighed in on the rest of the field in an interview with Sean Hannity that will air Wednesday night at 9pm EST.

Republican presidential candidate, former House Speaker Newt Gingrich gestures as he speaks, Tuesday, Nov. 29, 2011 in Bluffton, S.C. (Stephen Morton/AP)

According to the an excerpt from the transcript, here’s how Gingrich sees his GOP rivals:

“I can say that Michele Bachmann brings a lot to the table. Herman Cain is a very good businessman who has been a very Republican spirited. I helped to point him to the Jack Kemp tax reform commission back in the ‘90s. He’s a solid person in that sense.

Governor Romney is a great manager, has a terrific business career, would be, I think, far better than President Obama, you know. And you can go down the list.

I mean I think that these are -- Rick Santorum is a genuine expert on Iran and foreign policy and is probably the most deeply committed person on how do we rebuild the family as the base of American life. So I look at my friends and I think of them as my friends. I have one opponent, Barack Obama.

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