The real significance of the big press conference that Herman Cain’s new accuser held today is that the Cain boomlet hasn’t changed anything for Mitt Romney: He is still the clear frontrunner. That’s clearer now than it was earlier today, but this was true before the Cain boomlet, and it’s still true now that Cain is melting down.

But one thing has now changed: Auditions will commence anew for the role of The Other Candidate Left Standing — i.e., the conservative alternative to Romney.

Which brings up a strategy question: will most of the candidates finally turn to attacking Mitt Romney?

So far, Romney has benefited by a strange but understandable dynamic: all the other candidates have been competing to be the other candidate in the race, and so they’ve often trained their attacks on whoever is temporarily receiving a bump in the polls, but not on Romney. So Michele Bachmann, Rick Perry, and Herman Cain have all had turns as pin-cushion, but other than Perry — who has been spectacularly bad at it so far — none of them have really focused on the Mittster.

This is what you should keep an eye out for at Wednesday night’s debate. There’s plenty of material to attack Mitt, from Obamneycare to abortion and on down the line. Really, anyone who actually wants the nomination should be going after Romney. Those who don’t attack Mitt will just be confirming that they’re vanity candidates or business plan candidates or just pushing their issues; they clearly have little interest in actually winning the GOP nomination.

Mitt Romney has been lucky so far. His opponents have been inept and they’ve had sensible strategic reasons to avoid attacking him. But perhaps his good luck is finally about to run out. Iowa is getting closer, and if Romney’s opponents are ever going to derail him, the next eight weeks are their last chance to do it.