Call this the "GOP Strikes Back" edition. Four new polls were released today, none of which showed Democrats in a position better than previously. Further, because these polls were of a couple "swingier" states, the model has reacted more aggressively away from the Democrats. As it stands, Republicans have a 56% chance of winning the Senate, up by more than 4% from yesterday's 51.9%.
The polls released today for the most part gave more weight to information we already had. For example, in Alaska, polls have increasingly been showing Dan Sullivan leading Senator Mark Begich. However, because there were previously fewer polls showing this phenomenon, the model doesn't weight them as much. When numerous polls show the same result, the model weighs that result more heavily, thus putting Begich at only a 28% chance of re-election, which is down from 36% yesterday.
The same can be said for Michigan's Gary Peters. Yesterday, two polls showed Peters with a slim but consistent lead against his opponent, Terri Lynn Rand. While the lead was smaller than previous polls had shown, there was still enough uncertainty to not yet place extra weight on the new polls. However, a survey released today again showed only a two point lead for Peters. His chances of winning have now dropped to 83% from 88%.
Two final polls of note: Public Policy Polling showed Arkansas' GOP Rep. Tom Cotten leading Senator Mark Pryor by six points, and a Reuters/Ipsos poll had Senate Minority Leader Mitch McConnell leading his challenger, Alison Lundergan Grimes, by four points.
The latter poll is completely in line with expectations, but the PPP poll shows the largest lead Cotton has had against Pryor all cycle. What this means for the model is that Pryor's chances of winning have diminished to only 24%.