There are a host of organizations that track congressional elections and offer lists of the most competitive Senate races. You can consult Real Clear Politics' list, which is backed up by polling data, or peer into Larry Sabato's Crystal Ball for a political scientists' perspective. But perhaps the best indicator for which elections are most competitive comes the parties themselves.
The National Republican Senatorial Committee (NRSC) committed itself to an early ad-buy this week, penciling in $25 million to spend on ads in six different Senate races. The blitz won't start until after Labor Day, so the group still has time to cancel or reconfigure how that money is spent, but it provides an early glimpse at the seats at play. With the current breakdown in the Senate at a 53–47 advantage for Democrats, Republicans will need to swing four seats their way, or three seats if they win the presidency and the vice president's tie-breaking vote. Here are the six races where the NRSC is planning to commit its early funds, per Roll Call:
- $5 million in Wisconsin for the open-seat race to succeed retiring Sen. Herb Kohl (D).
- $5 million in Missouri to defeat first-term Sen. Claire McCaskill (D), who faces an extremely tough re-election race.
- $3.5 million in Montana to defeat Sen. Jon Tester (D), another first-term Senator with a hard re-election ahead of him.
- $5.5 million in Virginia for the open-seat race, where former Sen. George Allen (R) and former Gov. Tim Kaine (D) are locked in a highly competitive contest.
- $3 million in Nevada, where appointed Sen. Dean Heller (R) is seeking a full term against the presumptive Democratic nominee Rep. Shelley Berkley.
- $3 million for the open-seat race in New Mexico, where former Rep. Heather Wilson (R) and Rep. Martin Heinrich (D) are on track to face each other in November.
It's noteworthy that a large chunk of that money is going to defend the Republican seat in Nevada. At the beginning of the cycle, all the evidence pointed toward disappointing results for Democrats based on the number of seats they need to defend-23 Democrat-held spots compared with just 10 for the GOP. But a number of the Republican seats have trended against the party. In addition to Nevada, Massachusetts and Maine could easily swing to the Democrats. In Massachusetts, Elizabeth Warren is running strong against incumbent Scott Brown, easily outpacing him in fundraising and running about even in polls. A Rasmussen survey this week found Warren ahead of Brown by one point. With Olympia Snowe retiring in Maine, the early expectation is that independent Angus King will take the seat, and though King hasn't committed to caucusing with either party, his support for Obama and his critiques of Republican policy indicate that he might side with Democrats should he win this fall.
Still, it will be an uphill battle for Democrats. The NRSC left North Dakota and Nebraska off the list in their prospective buy. Both states trend Republican in national elections and with the two elder Democrats retiring in both instances, they could be easy gets for Republicans.
