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.)

Of the 11 most competitive races, the three models all agree on 10 of them. The lone outlier is Kansas where Sen. Pat Roberts (R) is facing off against Greg Orman (I). Both FiveThirtyEight (58 percent chance) and Leo (55 percent) give Orman the advantage while Election Lab says Roberts has a 79 percent chance of victory.

Kansas is by far Democrats' best potential pickup opportunity -- although Orman refuses to say which party he would caucus with in Washington -- according to the models. No model gives Republican businessman David Perdue less than a 73 percent chance of winning the Georgia open seat and Mitch McConnell's (R) probability of winning a sixth term are between 85 percent (FiveThirtyEight) and greater than 99 percent (Election Lab).

Similarly, the models all agree that one-time Republican pickup opportunities in Michigan, New Hampshire and North Carolina are increasingly far-fetched -- though it is worth noting that recent poll data in the former two suggest tightening races.

The overall picture 36 days out from the midterms? Republicans are in an increasingly good place in their march to a six-seat pickup.