Early last month Tim Pawlenty vowed not to be the first candidate to go negative. (“I’ve said I’m going to abide by Reagan’s 11th commandment and not whack other Republicans or at least not be the first one to whack them. I do remind people I’m an old hockey player, and if elbows start getting thrown, I’m not averse to getting in the corner and start throwing some myself. But we’re not going to start that process.”) Forget that. A month later, still lagging in single digits and badly trailing Mitt Romney in the money race Pawlenty is nixing “Minnesota nice.”

On “Meet the Press” on Sunday, Pawlenty went after Rep. Michele Bachmann (R-Minn.) who has passed him in the polls in Iowa:

Well, I like Congresswoman Bachmann. I’ve campaigned for her, I respect her. But her record of accomplishment in Congress is nonexistent. It’s nonexistent. And so we’re not looking for folks who, you know, just have speech capabilities, we’re looking for people who can lead a large enterprise in a public setting and drive it to conclusion. I’ve done that, she hasn’t. . . .

We’re both conservatives. I think the main difference is this, I’ve got executive leadership in a public setting with a record of accomplishment and results under difficult and challenging circumstances, and she has served in Congress. And in that regard, her record of accomplishment is, you know, like I said, nonexistent.

He also unloaded on Romney, whom he shied from confronting face-to-face in the New Hampshire debate: “I think if you’re going to prosecute the political case against President Obama and one of the top three or four issues is going to be the direction of the country in health care, it’s going to be very difficult for our nominee to be one of the co-conspirators or co-designers of that.”

In measured tones Bachmann’s campaign responded later in the day, which:

“This is an election about the future of our nation — one where voters will have to decide who is best equipped to lead our nation by looking at our records, as well as our vision for the nation. Instead of negativity, I want to focus on my accomplishments.

I have fought the cap-and-trade agenda, rather than implement it, and I will work to end cap-and-trade as President of the United States. I stood up against President Obama’s support of the $700 billion bailout rather than defend it.

I was a leading voice, fighting against Obamacare and the unconstitutional individual mandates; I did not lift my voice in praise of it. My message brought tens of thousands of Americans to Washington D.C. to oppose Obamacare. As President I will not rest until Obamacare is repealed. And I will not vote to raise the debt ceiling.”

Who came out ahead on that exchange? It’s not clear Pawlenty is going to make headway claiming that Bachmann doesn’t have a “record” when her agenda is to stop President Obama’s agenda. And Bachmann’s response is likely to endear her to the hard-core base (which wants to fight Obama tooth-and-nail) that will boost her results in Iowa.

Nevertheless, an associate close to the campaign confirms that Pawlenty want to get more aggressive with both Bachmann and Romney.

But is there a danger here that he will look desperate or lose his own persona, which doesn’t specialize in personal attacks? A supporter of an opponent says with a shrug, “I guess it’s an all-of-the-above strategy. Just claw at anything and everyone ahead of him.”

Dana Perino, President George W. Bush’s White House press secretary, isn’t surprised by the change in approach: “At some point in a primary campaign, a candidate has to start defining his or her opponents. None of them can go on without ever offering a critique, and they can try to do so constructively and without sharp elbows.” She adds, “Governor Pawlenty’s comment about Representative Bachmann comes as the race in Iowa is becoming more heated, and I suppose the governor’s internal polling shows what the rest of us are reading — that she is gaining in Iowa and could win it. If that’s the case, it’s not that surprising that he’d start to draw contrasts when asked to do so. I would imagine she expects that and doesn’t take it personally.”

Pawlenty at this point has nothing to lose. Roll Call reported: “A pair of struggling GOP presidential hopefuls, former Sen. Rick Santorum (Pa.) and former Minnesota Gov. Tim Pawlenty, fought for the title of most popular campaign underdog in separate television appearances Sunday.” Being paired up with a marginal candidate like Santorum is adding insult to injury. And that’s reason enough to take some chances.

Pawlenty, however, should keep a few of things in mind. First, he’s going to have to carry through with his attacks in a debate setting without looking nasty or, in the case of Bachmann, like a bully. Second, he risks offending the Tea Party set, which swoons in Bachmann’s presence. It’s one thing to try to woo her base; it’s quite another to insult her. That might well backfire. He risks having Bachmann and Romney return fire, she from the right and he from the perspective of a businessman who never embraced schemes like cap-and-trade.

All that said, if Pawlenty doesn’t throw the dice now it may be too late.