Via Taegan Goddard, who notes that Glen Bolger is a GOP pollster, with the understandable implication that he may be somewhat inclined toward irrational exuberance.  Bolger brings the numbers to support his conclusion of a building wave that may be more massive than people have predicted.  Traditionally safe Democratic seats won’t be impacted as much, but anything competitive has a strong chance of flipping to the GOP:

Last week, I conducted a national survey for American Action Network.  The two key political environment questions show the significant opportunity Republicans have this year.  While the overall numbers on the President’s approval rating and the generic ballot are good news, one key crosstab highlights the wave that is building.

The generic ballot shows Republicans leading 44%-39%.   Besides all of the usual regional crosstabs, we also broke it out by the type of district.  We looked at the sample in the 66 Democratic INCUMBENT districts that Charlie Cook lists as either toss-up or leaning Democratic at the time of the survey.  In that key crosstab of Swing Democratic Incumbent Seats, the Republican lead grows to 49%-31% on the generic ballot.  That is a very powerful crosstab that says the wave is coming.

Among the remaining Democratic districts (Likely/Safe Dem, and open seats), the generic ballot is an unsurprisingly 33% GOP/51% Dem — a sign that the historically safe Dem seat will remain so, while the swing seats will be a bloodbath.  By the way, all of  in the GOP held seats, the generic is the reverse of the base Dem seats — 52% GOP/32% Dem.  Very few, if any, Republican incumbents will be defeated.

Given that the overall generic gap falls into the middle of most polling these days, this seems at least a reasonable outcome from the polls.  The approval ratings for Barack Obama also appear to fall within the mainstream of polling, with an over 46/51 — but a 40/57 in these contested seats.  Bolger also notes that John McCain won many of these districts in 2008 or at least did better than he did nationally.

Suburban and rural voters have stampeded away from Democrats in this cycle, going 48/36 and 51/30 for the GOP, respectively.  That has the most pressing implications in the Rust Belt and Midwest, which Bolger calls “a killing field” for Democrats this year.  He predicts a massive sweep from western Pennsylvania to the Rockies for Republicans, and one that rolls down into the South as well.

Where does that put the floor?  Not all 66 of these races will necessarily flip, but by the same token, these may not be the only races that wind up being competitive, either.  It’s at least safe to say that this looks like it could be another 1994.