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In his latest election forecast for FiveThirtyEight, stats guru Nate Silver predicts that the GOP is a "slight favorite" to take control of the Senate this November. Silver estimates Republicans have about a 60 percent chance to pick up at least the six seats necessary to win back the upper chamber, though he cautions that only four races are "clearly leaning their way," and offers the standard disclaimer that the elections are still seven months away — a lifetime in electoral politics. As of now though, Silver's model shows the GOP heavily favored to pick up seats in South Dakota, West Virginia, Montana, and Arkansas, with Louisiana leaning Republican and North Carolina a straight toss up.

As for the accuracy of Silver's past political prognostications, he correctly predicted the electoral college outcome in all 50 states in the 2012 election, four years after going 49 for 50 in the previous cycle.