There’s a general consensus that Republican Charlie Summers is going to need a solid performance from his Democratic counterpart Cynthia Dill if he’s going to win the U.S. Senate seat.

The reason is that Dill could help split the progressive vote with independent Angus King, thereby narrowing King’s advantage and giving Summers a path to victory in November.

But the question remains: How can Summers and his Republican allies prop up Dill in an effective, yet subtle way?

Time will tell, but a couple of registered Democrats have written to say that they were recently polled by a group that was trying to make sharp distinction between King and Dill. The exact wording of the questions isn’t clear, but the readers had the distinct impression that the callers were probing for fissures on progressive issues that could be exploited by Republicans. 

So who is conducting this polling? That’s not clear. Lance Dutson, Summers’ campaign manager, said it’s not his team. Dill doesn’t appear to be doing it either, which could be because the campaign may not have the financial resources to conduct baseline or push polling.

That leaves the possibility that outside groups with an interest in seeing Summers elected are behind the polling. The conventional wisdom is that the U.S. Chamber of Commerce will conduct polling to see if the $400,000 ad buy against King has made a difference. Other groups may also be testing the waters. 

Time will tell, but if one thinks it odd that a Republican would help a Democrat, or vice versa, one need only to look to Missouri to find a recent, and timely, example of how it can work.

Earlier this year Democratic U.S. Senate candidate Claire McCaskill took the unusual step of attacking Republican Todd Akin‘s rivals during a GOP primary with three GOP candidates with about $1.5 million in television adds. People questioned why McCaskill would spend the money.

Now, however, McCaskill’s camp is looking pretty shrewd for talking up Akin’s conservative credentials, which it just so happens, included his hard-line stance on abortion.