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Iowa's key Senate race may be slipping away from Democrats, as a new Des Moines Register poll released late Saturday gave Republican Joni Ernst a seven-point lead.

In the poll, Ernst led Rep. Bruce Braley (D) 51 percent to 44 percent among likely voters. The race has generally been trending in Ernst's favor over the closing weeks of the campaign, and she's now a two-to-one favorite to win, per The New York Times' latest forecast.