Nate Silver, the human political calculator for the New York Times and the blog FiveThirtyEight, is up with a post touting the Evergreen State as the “most important state of all” in terms of GOP chances for a Senate takeover. The numbers wonk ran thousands of simulations, in which a virtual election is carried out on a computer using various polling data. And though the conclusion is riddled with qualifiers, the take home is that without Washington, the upper chamber almost certainly stays blue. Silver writes that the other key Senate races for the GOP are West Virginia and California, in that order of importance. Winning in Washington, however, won’t be easy. As we reported earlier this morning, polls in the state are all over the map. And while most show the race tightening somewhat, only Rasmussen has Republican challenger Dino Rossi ahead of incumbent Sen. Patty Murray–and that’s only by a point.On balance, the Republicans’ chances of taking the Senate remain low, overall–12 to 13 percent, writes Silver.But stranger things have already gone down this election cycle and a lot can happen between now and Tuesday.