Today, most political pundits and election handicappers are suggesting that Republicans will successfully wrest the Senate majority away from the Democrats in the November election, but is the GOP victory path really so clear?
To recap the situation for both sides, Democrats are risking 21 of the 36 in-cycle Senate seats, and the Republicans 15. The GOP needs a net conversion of six Democratic seats to claim the majority. Therefore, Democrats can lose five of their own seats and not gain a single Republican state, yet still retain control. Because Vice President Joe Biden (D) breaks any Senate tie vote, the Dems will retain the majority if the partisan division is 50-50.
Building the Republican and Democratic victory models from scratch, the Democrats begin with 34 hold-over seats of the 55 they currently possess. The Republican ratio is 30 (hold-over) to 45 (total seats).
Today, it appears that 10 of the 21 Dem in-cycle seats are well beyond any margin of polling error: Delaware (Coons), Hawaii (Schatz or Hanabusa), Illinois (Durbin), Massachusetts (Markey), Minnesota (Franken), New Jersey (Booker), New Mexico (Tom Udall), Oregon (Merkley), Rhode Island (Reed), and Virginia (Warner).
Republicans look to be headed for victory in 16 seats, including three Democratic opens: Alabama (Sessions), Idaho (Risch), Kansas (Roberts), Maine (Collins), Mississippi (Cochran), Montana (Daines converting from Walsh), Nebraska (R primary winner), Oklahoma (Inhofe), Oklahoma (R nominee), South Carolina (Graham), South Carolina (Scott), South Dakota (Rounds converting from Johnson), Tennessee (Alexander), Texas (Cornyn), West Virginia (Capito converting from Rockefeller), and Wyoming (Enzi).
The three Democratic retirements in Montana, South Dakota and West Virginia are critical to Republican majority chances. Sweeping this trio of states will put them in launching position to assume Senate control, so it is imperative, from the GOP perspective, that the candidates run mistake-free campaigns in each place.
Counting the three conversions, Republicans would then have clinched 46 seats as compared to the Democrats’ 44, with 10 undecided. Eight of the 10 are now in control of the Democrats, meaning the Republicans would have achieved their early cycle goal of expanding the political playing field. It is also possible that three more states could conceivably become competitive before November arrives, each in Democratic control. Those are: Minnesota (Franken), Oregon (Merkley), and Virginia (Warner).
Republicans could hit a major bump in the road if they stumble in just a few primaries, resulting in weak general election candidates, such as what happened in both 2010 and 2012, in certain instances. The situation in Georgia and Mississippi, and potentially Kansas, could yield primary upsets, which may well change the general election picture.
Assuming no surprises in the aforementioned 26 campaigns (16 R wins; 10 D victories), the majority will be decided in the 10 most hotly contested general election races. They are: Alaska (Begich), Arkansas (Pryor), Colorado (Mark Udall), Georgia (open Chambliss), Kentucky (McConnell), Iowa (open Harkin), Louisiana (Landrieu), Michigan (open, Levin), New Hampshire (Shaheen), and North Carolina (Hagen).
Of these 10, Republicans gain the majority by winning any five races, exactly half of the subset. Doing so would propel them to 51 seats. Democrats retain control by winning any six of the 10. A half-dozen victories within this group would allow them to land exactly on the 50 seat mark, the bare minimum Democrats need to retain the majority.
Once more, the importance of Montana, South Dakota, and West Virginia emerges for Republicans. Converting the seats actually permits them to win a smaller number of the battleground states than their counterparts, even though the former begins in a distinct minority. Failing to sweep the aforementioned three returns the edge to the Democrats, and greatly diminishes GOP chances of seizing majority control.
Should the playing field expand to include Minnesota, Oregon, and Virginia, then Republican chances grow even stronger because all are Democratic-held states. If the battleground number does increase, then the GOP would only need to win five of the 13 to gain control, whereas Democrats would be forced to win nine to retain power.
Today, it is realistic to project that both parties will fall between 49 and 51 seats. Forecasting GOP gains is clear, but whether their win total is high enough to establish a new majority remains murky.