Of course, many Democrats believe — or hope — that next year’s Republican primary voters will nominate a candidate from far outside the mainstream, just like they did in several key Senate races last year. But that’s probably expecting too much — especially because we now have evidence that the conservative establishment is very focused on not fielding an unelectable candidate next year. This (partly) why so many influential conservative voices have spoken up in an effort to marginalize Donald Trump in the last week. Eric Cantor, Charles Krauthammer, George Will, Stephen Hayes, Rich Lowry and Karl Rove — to name a few — have all dismissed or disparaged Trump recently. It is not a coincidence that they began speaking up only when Trump surged to the top of GOP polls and began looking (to some) like he might actually run for president. They understand the short- and long-term threat that Trump and his birtherism pose to their party, and by turning on him, they are sending a clear signal to other influential conservatives and to the conservative masses. It is this exact sort of effort that has helped them marginalize Palin within the party. (Notably, the new poll finds that just five percent of Republicans now volunteer Palin’s name as their ’12 choice.)

The implications of this are obvious: If a clearly unelectable candidate emerges as a viable threat to win the GOP nomination, conservative voices with real credibility on the right will step in to steer the rank-and-file in another direction. In other words, it still seems likely — for all of the zaniness in the air — that the GOP will end up nominating a candidate like Romney or Pawlenty next year, someone generic enough to take advantage of a lousy economy (if the economy remains lousy).