This article has been updated to include the latest polling data.
The battle for control of the legislative branch ultimately comes down to the fight for a handful of Senate seats. Four weeks out, do the polls predict a blue wave or blue washout in the most powerful of the two chambers?
According to RealClearPolitics’ average of the key polls, seven Senate seats could potentially go either direction in the fight for the 51-seat majority (down from nine a month ago). The other 93 seats are either not up this cycle or at least lean heavily to one of the parties.
Democrats have 37 seats total that are either not up or are considered “safe” by pollsters. RCP gives Democrats another three seats that are “likely” to go their way and another four that “lean” Democrat, making the total 44 seats that at least “lean” in the direction of the Democrats.
Republicans are in far better shape, with 46 seats either not up or “safe,” one seat that’s “likely” to go their way, and another two seats leaning their direction, giving them a total of 49 seats that are at least leaning Republican (a two-seat improvement from a month ago).
If pollsters are correct about the seats firmly in either party’s grasp, to seize control of the Senate, Democrats would need to pick up all seven of the highly competitive seats, as Republicans have the tie-breaker with Vice President Mike Pence.
Below are the seven “toss up” races, listed in the order of the tightness of the race, according to the most recent polling data:
Missouri — Republican +0.4% (as of 10/2)
- Claire McCaskill (D)* 45.6%
- Josh Hawley (R) 46%
Nevada — Democrat +2.3% (as of 9/29)
- Jacky Rosen (D) 45.3%
- Dean Heller (R)* 43%
Florida — Democrat +2.4% (as of 9/30)
- Bill Nelson (D)* 47.6%
- Rick Scott (R) 45.2%
Indiana — Democrat +2.5% (as of 10/2)
- Joe Donnelly (D)* 43.5%
- Mike Braun (R) 41%
- Lucy Brenton (L) 7%
Tennessee — Republican +2.7% (as of 10/5)
- Phil Bredesen (D) 45%
- Marsha Blackburn (R) 47.7%
Montana — Democrat +3% (as of 9/22)
- John Tester (D)* 48.3%
- Matt Rosendale (R) 45.3%
Arizona — Democrat +3.4% (as of 10/5)
- Kyrsten Sinema (D) 46.4%
- Martha McSally (R) 43%
Two seats that were considered “toss ups” a month ago, RCP now considers safely Republican:
Texas — Republican +6% (as of 10/5)
- Beto O’Rourke (D) 43.3%
- Ted Cruz (R)* 49.3%
North Dakota — Republican +8.7% (as of 10/2)
- Heidi Heitkamp (D)* 42%
- Kevin Cramer (R) 50.7%
In the House, RCP currently gives Democrats 205 seats that at least “lean” their direction and Republicans 198 (that’s an 11-seat improvement from Republicans over the last month). Pollsters currently deem 32 seats to be true “toss ups.” A total of 218 seats are required to achieve a majority in the 435-seat House.