Tuesday, November 2, 2010

Final Senate and Gubernatorial Projections

With only a few polls yet to trickle in, and election day having arrived, it seems like a good time to make my final projections for Senate and gubernatorial elections.  Just a quick reminder that these forecasts are based solely on pre-election polls taken in the last forty-five days of the campaign and the relationship between polls and election outcomes in the last two election cycles.

Senate Projections

Based on point estimates alone, Republicans are projected to gain eight Senate seats.  However, if I could be allowed a bit of wiggle room, three of those races (Colorado, Illinois, and Nevada) have the Democratic candidate barely losing, pulling at least 49% of the two-party vote.  Clearly, any underestimation of the Democratic support in these states could flip them back into the Democratic column.  

Having said that, the poll-based forecasts also show Democrats holding on to both West Virginia and Washington with slight margins, right around 51% of the two-party vote.  So, in these cases, even a slight over estimation of Democratic support could move these states into the Republican column.  The bottom line, then, is that the election could easily produce anything from a modest (given the hyperbole of late) Republican pick up of five seats to majority-grabbing pickup of ten seats.  I'm putting my money on +8 Republican.

 Gubernatorial Projections

The Republican party also stands to gain a number of governorships.  Again, going just on point estimates, I project that six Republican governorships fall to the Democratic column and one flips to an independent (though formerly Republican) candidate, Lincoln Chafee, of Rhode Island; but these  projected losses are more than offset by flipping twelve Democratic governorships to the Republican column.  At the end of the day, this represents a net gain of five governorships for the Republican party.

As with the Senate projections, however, a handful of states are close enough right now that even slight errors in the right direction could change the outlook somewhat.  For instance, I could see Republicans doing just a bit better than expected in Vermont, Oregon, and Florida and turning those  states from projected Democratic wins to actual Republican wins.  I think Florida in particular is truly up in the air.  At the same time, the Democrats could pick up another governorship in Rhode Island if polls are underestimating Democratic support in this three-way race,  and might be able to retain the governorship in Ohio if Ted Strickland is able to carry recent momentum into election day.   I'm not trying to hedge here, at least not a lot, but I do want to emphasize that as accurate a predictor as pre-election polls are, predictions of very narrow victories could end up being very accurate but still call the wrong winner.

We'll know soon enough how things turn out.  While the accuracy of these projections is not among the most important considerations tomorrow,I am anxious to see if the track record of pre-election polling holds up.  I'm betting on it.

*The Democratic vote share in Colorado and Rhode Island are estimated relative to independent/third-party candidates (Tancredo in Colorado and Chafee in Rhode Island) who are out polling the third-place Republican candidates.