How many Senate seats will the GOP gain this fall ? Can the GOP retake the Senate ? And which seats are likely to flip ? Unlike our discussion of House gains, there has been a decent volume of polling in nearly all of the Senate races, with some races having several polls done each week by different polling organizations. The Senate also differs from the House in a very major way in that not all seats are up for re-election this year. Typically, a third of the seats are up in any given election cycle, but this year, we have an unusually large number (37) of seats up for re-elections, because (1) not only did President Obama and Vice President Biden come from the Senate, but they also chose sitting senators for two Cabinet positions: Hillary Clinton for Secretary of State and Ken Salazar for Secretary of the Interior, and (2) the untimely death of Robert Byrd of West Virginia created the need for a special election.

Since there has been a decent amount of polling done (as of today, polls have been released for all but the Hawaii Senate race) , we therefore have a better feel for how the race for the Senate is progressing. The most important part of the discussion is understanding what can happen on Election Night, because partisans on either side can give overoptimistic predictions that are not grounded in reality. Currently, Democrats control 59 seats (this total includes that of Socialist Bernie Sanders of Vermont and Independent Joe Lieberman of Connecticut), while the Republicans control 41 seats. Of the 37 seats on the ballot this year, 19 are held by Democrats, and 18 are held by Republicans. Even if every Democratic incumbent were defeated, the best the Republicans could do would be to control 59 seats.  To best understand the race for the Senate, we are therefore analyzing four different pieces to the puzzle: (1) incumbent Republicans, (2) Republican held open seats, (3) incumbent Democrats, and (4) Democratic held open seats.

Incumbent Republicans – there are 10 Republican incumbents up for re-election this cycle. All 10 lead in the polls with double digits and with more than 50% of the vote. In a “wave election” like we think this one will be, we see little causing that to change between now and November;

Open Seat Republicans – Back in early 2009, there was a wave of six Republican retirements which, when combined with two primary defeats (Lisa Murkowski in Alaska and Bob Bennett in Utah), led to initial concern that Democrats might expand their (at the time) filibuster-proof bench of 60 Democratic senators. Those thoughts are now well in the past. In five of those eight (Marco Rubio in Florida, Jerry Moran in Kansas, Roy Blunt in Missouri, Rob Portman in Ohio, and Mike Lee in Utah) seats, the Republicans are well in the lead, with either double digit poll leads or with poll numbers above 50%. And since we believe this is a wave election, we believe all of the Republican candidates will be pulled to the finish line. There are only three seats in this category that aren’t completely locked down yet: (1) in Alaska, defeated incumbent Lisa Murkowski is running as a write in, although at this point it seems like any oxygen she is consuming comes at the expense of the Democratic candidate, (2) in Kentucky, libertarian Rand Paul has led in every poll, but those leads are not overwhelming (his average poll lead is currently 49-45%). While we think the strong anti Obama sentiment in Kentucky will pull him through in the end, we can’t totally ignore this race, (3) New Hampshire Republicans held their primary just two weeks ago and picked a more establishment candidate (Kelly Ayotte) . While she’s certainly favored to win, the only polling we’ve seen since the primary shows her with an average poll lead of 49-44%; decent, but not overwhelming.

Open Seat Democrats – In wave elections (1980, 1994, 2006, 2008), open seats are the seats which one party will typically sweep. What is not generally remembered today is that six of the eight seats gained on Election Day in 1994 were open Democratic seats. This year, there are nine open Democratic seats, which by itself would enable the Republicans to get to 50 seats. However, we are not expecting that many Republican pickups from this group of Democratic held seats, because of a combination of strong Democrats recruited and/or weak Republican nominees. In fact, if we look at each of the nine open Democratic seats, we see varying likelihoods of the Republican chances in each state. For starters, the open seat races in North Dakota (68-25% average Republican lead) and Indiana (50-34% average Republican lead) are pretty much assured pickups for the Republicans.  Colorado (49-45% Republican) and Pennsylvania (49-42% Republican) are likely Republican pickups, but those states that voted for Obama, so Democrats aren’t totally out of the running. Republicans recently have begun to gain some traction in Illinois, but the 42-39% poll lead the Republican has is very shaky, and it’s important to remember that this is Barack Obama’s old Senate seat – the Democratic nominee will have the finds to compete. The next two seats are leaning Democratic, but their primaries were held late, so there is still time for the Republican candidates to gain momentum. In West Virginia, the Republican only trails the popular Democratic Governor 45-47% in a state where the Obama name is toxic, and in August, the Democrat lead by double digits. In New York, the Democratic incumbent leads 50-39%, although if you remove a Siena poll that used registered voters as its sample, her lead is 47-42% – hardly a vote of confidence in Democratic dominated New York. Finally, Connecticut and Delaware are open seats that would seem to be out of reach for Republicans now due to the candidates nominated. In Connecticut, however, the Democrat leads 51-45% in the polls – significantly down from a 20 point lead he had two months ago. In Delaware, the Democrat leads 54-40%, due to unfavorable publicity that has come out about the Republican nominee. However, the Republican who lost the primary is considering running as a write-in, which would be a game changing event in the Republicans’ favor.

Open Seat Democrats – Finally, there are 10 Democratic incumbents with varying degrees of electoral security. Normally, incumbents are pretty safe, but in an election year like this one, anywhere from 1-5 Democratic incumbents may be defeated. In Arkansas, 12 year incumbent Blanche Lincoln is pretty much finished politically: with about a month to go, she still trails 34-53% in the polls. Since Wisconsin held its primary on September 14, 18 year incumbent Russ Feingold has seen the bottom fall out of his campaign, and he trails 43-51% in the polls – a disastrous showing in a state that last voted for a Republican senator in 1986.  The next incumbent is 24 year Senate veteran Harry Reid (who served in the House for 4 years before that), who has been in a neck and neck race since the June primary; he currently leads 45-44%. The next two races involve 18 year female Democratic incumbents in California and Washington, respectively. Republicans nominated attractive (and well financed) opponents to Barbara Boxer and Patty Murray, and in early summer polling, both races were neck and neck (in fact, in an all party primary in Washington, Senator Murray only got 46% of the vote). However, those races have been trending Democratic lately:  Patty Murray leads 51-45% in Washington, while Barbara Boxer leads 48-43% in California. While Republican voter enthusiasm can close the gap in both of these races, early voting is around the corner in both states, so the question is whether the Republican challengers can turn their poll numbers around while early voting is going on. Finally, the last four Democratic incumbents are secure enough electorally and/or are in Democratic enough states to where we are not expecting any upsets: Chuck Schumer in New York leads 57-34%, and both Ron Wyden in Oregon and Barbara Mikulski in Maryland lead 54-38%. We have no polling data in Hawaii, but 48 year incumbent Daniel Inouye is as close to safe as they come. Curiously, in all four of these states, there are competitive Governor’s races appearing on the ballot at the same time as the Senate races, so there is always the possibility of straight ticket voting providing an assist to the Republican Senate candidates if somehow these races got any closer by Election Day.

In closing, the answer to the “can the Republicans retake the Senate” question is a “maybe.”  The first three pickups (Arkansas, Indiana, North Dakota) are pretty much a given.  The next three pickups (Colorado, Pennsylvania, and Wisconsin) are likely but not guaranteed.  From there, there is a batch of six Senate seats (California, Illinois, Nevada, the Clinton seat in New York, Washington, and West Virginia), where the Republicans would need to win at least four to gain control of the Senate. A crucial point needing to be made here is that since Vice President Biden can cast a tie breaking vote, Senate control by the GOP can only be attained with 51, and not 50, votes. Finally, we believe that five Democratic incumbents (Hawaii, Maryland, the Schumer seat in New York, Oregon, Vermont) are close to untouchable. The remaining two open seats (Connecticut and Delaware) are likely, but not guaranteed, Democratic.

Finally, it’s worth noting that early voting has already commenced in five states, with new states starting their early voting as we get into October. That means that what campaigns are doing with their media and grassroots as we speak will be crucial in terms of getting every last vote. But it’s important to realize that regardless of what happens, we are realistically looking at a Senate consisting of anywhere from 44-55 Republicans.

Attached is a link showing the weighted average of poll results for Senate races for the last 14 days.