The first primary ad attacking a fellow Republican directly comes from Rep. Michele Bachmann’s super-PAC. Here is the ad:

This is a third-party ad, so there should be no coordination with the Bachmann campaign. However, it doesn’t take a political genius to figure out that she has the most to gain by knocking Perry down a peg and the most to lose if he continues to solidify his support. She is losing ground quickly and needs to prevent the race from being a two-man contest.

In the run-up to the last debate and in the debate itself she flicked away Tim Pawlenty’s barbs and rattled off a list of his conservative heresies. Now Perry is no Tim Pawlenty, but he also hasn’t taken part in a presidential debate. The opportunity for Bachmann to undercut his momentum, I suspect, won’t go to waste.

I think attacking him on spending may not be the strongest gambit. However, he is vulnerable on issues on which she can capi­tal­ize, most especially his stance on immigration and his reversals on gay marriage and mandatory HPV vaccination. The challenge for Perry is not only to dispel these concerns and reassure establishment Republicans, but to do so without appearing to be either overly defensive or a bully. It’s not an easy task.

A GOP veteran yesterday described Bachmann to me as an “episodic politician.” She makes and creates big moments. She wowed the punditocracy in the debates. She released boffo ads in Iowa. She won them over in Ames. Now she needs to do it again in the debate and in the South Carolina forum on Monday. She has billed herself as the “consistent conservative.” Well, that must mean the others are “inconsistent” conservatives.

Unlike Pawlenty or Mitt Romney, Bachmann has the conservative bona fides to attack Perry for these deviations. Whether she has the skill to land a punch is another matter. But I’m betting we get some fireworks. With Bachmann on the stage I’d expect nothing less.