Yesterday’s Quinnipiac poll showing Michele Bachmann at 15 percent—only ten points behind Mitt Romney—may not have been surprising, but it has changed the dynamic. What was once the race between Not Romney and Not Palin has become Not Romney vs. Not Bachmann.

Conservative grassroots would love to have a serious challenger to Romney. Ironically, however, their search helps solidify Romney’s early lead because they can’t seem to settle on one that could peel off any of Romney’s establishment support.

Additionally, as was noted at Red State, the more anti-Romney candidates get in the race, the more diluted the anti-Romney coalition becomes:

There is a lot of money on the sidelines waiting to find who is going to be the legitimate leader of the anti-Romney coalition. Rick Perry getting in delays finding that leader, keeping that money on the sidelines, keeping Mitt Romney on top. It really is that simple.

The other side of the Rick Perry coin is that some believe Perry could be the one to encroach on Romney’s monopoly of elite support. So Perry’s participation prevents existing candidates like Bachmann from solidifying grassroots support. And Bachmann’s candidacy has been suffocating Tim Pawlenty, who was supposed be the acceptable alternative to Romney.

All this has caused the frustration of the anti-Romney caucus to become palpable. Leading the way has been the Wall Street Journal, which wrote an editorial in May calling Romney “Obama’s running mate.” It called for an ideological conservative nominee, not a problem solver. Romney remains incompatible with where the heart of the conservative movement is today. And unlike Perry, Bachmann is actually in the race, debating well thus far, and gaining on Romney steadily. There may not be a not-Bachmann. There may be only Bachmann.