The odds of Republicans winning the Senate are growing
All three major election forecasting models saw an uptick in the likelihood of Republicans winning the six seats they need to retake the Senate majority over the past week, movement largely due to the party's strengthened chances in Alaska, Colorado and Iowa.
The most bullish model for Republicans is Washington Post's Election Lab, which, as of Monday morning, gives the GOP a 76 percent chance of winning the majority. Leo, the New York Times model, pegs it at 67 percent while FiveThirtyEight shows Republicans with a 60 percent probability. A week ago, Election Lab gave Republicans a 65 percent chance of winning the majority, Leo put it a 55 percent and FiveThirtyEight had it just under 55 percent.
All three models give Republicans very strong odds of winning the open seats in Montana, South Dakota and West Virginia as well as beating Sens. Mark Pryor (D-Ark.) and Mary Landrieu (D-La.). That would net Republicans five seats, one short of the number they need for the majority.
Of the rest of the competitive seats, Alaska is the biggest mover in all three models from a week ago. At that time, the models disagreed -- Election Lab (81 percent chance) and Leo (62 percent) gave Democrats the edge while FiveThirtyEight had Republicans at a 56 percent probability of winning. Today all three models align; Leo gives former state attorney general Dan Sullivan (R) a 72 percent chance of winning while Election Lab puts it at 71 percent and FiveThirty Eight at 68 percent. A series of polls released over the last week have shown Sullivan moving ahead of Sen. Mark Begich (D).
The other big change in Republicans' favor is in Colorado. Seven days ago , FiveThirtyEight's model called the state a true 50-50 tossup while Leo gave Sen. Mark Udall (D) a 55 percent chance of winning and Election Lab was even more optimistic for Udall at 67 percent. All three models today agree that Rep. Cory Gardner (R) is a (slight) favorite; FiveThirtyEight says Gardner has a 56 percent probability of winning while Leo is at 61 percent and Election Lab 66 percent. Like Alaska, several new surveys have show movement in Gardner's direction.
The models are also now in agreement -- unlike last week -- that Iowa's open seat tilts in state Sen. Joni Ernst's (R) favor albeit narrowly. Election Lab shows Ernst with an 83 percent probability of winning but that looks like the outlier as Leo has it at 61 percent and FiveThirtyEight at 56 percent. (The Real Clear Politics poll of polls has Ernst up by two points over Democratic Rep. Bruce Braley.)