In 2010, the most favorable environment for Republicans since the 1994 midterms, the GOP picked up 63 seats to take control of the House of Representatives. Nationally, the GOP won the House vote by 7%, after losing by 11% two years earlier. Republicans also gained six Senate seats that November, and they won a surprise victory earlier in the Massachusetts special election for Senate (Scott Brown). The extent of the GOP sweep carried over into governorships and state legislative seats. Republicans picked up Senate seats in solidly Democratic Illinois (Mark Kirk) and consistently Democratic Pennsylvania (Pat Toomey). Republicans also picked up seats in Arkansas, Indiana, Wisconsin, and North Dakota.
Republicans suffered three defeats in potentially winnable Senate races in 2010. Delaware, where Mike Castle, the only GOP candidate capable of winning statewide, was defeated in a party primary; Colorado, where Ken Buck lost narrowly to an appointed Democratic senator (less than 2%); and Nevada, where Sharron Angle was beaten fairly decisively by Harry Reid. In all three states, Tea Party candidates knocked off candidates in GOP primaries who likely would have run stronger in November. Only Nevada, among the three, might have remained with the Democrats regardless of the GOP nominee.
It was much worse for the GOP in 2012, as they not only did not gain Senate seats as was anticipated, but also lost a net two seats. Maine was lost when Olympia Snowe retired. Had Republicans gotten closer to a majority in 2010 — winning, say, Colorado and Delaware — Snowe might have run again and would have won easily. Scott Brown lost in Massachusetts, in large part because voters in the state (more of whom liked Brown more than his opponent, the churlish Elizabeth Warren) were concerned about Republicans gaining control of the Senate.
Two seats were outright blown following disastrous comments about abortion and rape by Todd Akin in Missouri (a very winnable seat against Claire McCaskill, in a state Romney carried by 10%) and by Richard Mourdoch in Indiana, who was looking to succeed Richard Lugar in a state Romney won by 9%. The biggest surprise was that the GOP candidate Rick Berg lost an open Senate seat by 1% in North Dakota, a state carried by Mitt Romney by 20%. Montana was another disappointment, with GOP nominee Denny Rehberg failing to knock off incumbent Jon Tester in a state Romney carried by 14%.
A good case can be made that with better candidates or messaging in the last two cycles, the GOP today would have at least 50 members in the Senate, not 45, where they will be after Cory Booker’s coronation in the New Jersey special election.
The 2014 midterms appear to be another target-rich environment for Republicans hoping to take control of the Senate. To accomplish that, it will take a pickup of six net seats. Until recently, most analysts looked only at the pickup opportunities and assumed that the GOP would easily defend the seats it already controlled in 2014. That is no longer the case. Both Kentucky and Georgia represent real pickup opportunities for Democrats, and while the GOP is currently favored in both states, neither is a safe seat and both will be expensive to defend.
On the plus side, the GOP has done a good job of recruiting candidates to run in states where Republicans have dominated in recent years. This is particularly true in Arkansas, where Representative Tom Cotton is at least 50-50 to beat Democratic Senator Mark Pryor, and in West Virginia, where Congresswoman Shelley Capito is favored to win the seat of retiring Senator Jay Rockefeller. These two states have shifted more dramatically towards the Republicans than any others in the nation the last 15 years, with Romney winning each by well over 20%. Republicans are also favored to win the open seat of retiring Senator Tim Johnson in South Dakota (Mike Rounds) and the open seat in Montana of retiring Senator Max Baucus, two more states Romney won easily in 2012. If Republicans win all four, and hold Georgia and Kentucky, then they need to win two of the following three to get to 51: Alaska (first-term Senator Mike Begich), Louisiana (Mary Landrieu), and North Carolina (first-term Senator Kay Hagan). Mitt Romney won Alaska, Louisiana, and North Carolina, the first two decisively.
How much risk is there for the GOP in defending Kentucky and Georgia? Georgia is an open-seat race, with Saxby Chambliss retiring. On election day 2008, Chambliss led by 49% to 46% over his Democratic opponent, but fell short of the required 50%, forcing a runoff. Chambliss won the second contest easily by 14%, with black turnout dropping far more than white turnout without Barak Obama on the ballot in the runoff. Georgia is a rapidly changing state, demographically. According to the 2010 census, it is 56% white, 30% black, and 9% Hispanic, though the white voting share is closer to 60%. Republicans win white voters by 3 to 1 margins, and lose even more decisively among minority voters. In recent statewide races, Republicans have won by 8-10% margins (Romney 8%, Governor Deal 10%). McCain won by 5% in 2008.