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Republicans have chalked up another win for the Senate, with state Sen. Joni Ernst winning the race to succeed retiring Democratic Sen. Tom Harkin.

With 67 percent of the vote reporting, Ernst has 51 percent support, against Democratic Rep. Bruce Braley with 46 percent. Ernst has been projected as the winner by multiple news outlets including ABC, Fox, and NBC.

Ernst broke through in her Republican primary in part with a series of quirky ads. One boasted of her experience castrate squealing hogs on the farm, proof that she could cut "pork" in Washington. Another used a gun at a firing range to ask voters to "give me a shot" against ObamaCare.

But perhaps the most consequential event in this campaign occurred back in March: Braley was caught on video telling an audience of lawyers at a fundraiser that if Republicans won the Senate, the state's senior Sen. Chuck Grassley, "a farmer from Iowa who never went to law school, never practiced law," would become "the next chair of the Senate Judiciary."

Braley issued a public apology soon after the video surfaced, citing his own parents' backgrounds as farmers. But in the long run, this misstep clearly helped Ernst pile up a huge advantage with rural Iowa voters. After that, Braley's efforts to portray Ernst as too right-wing simply could not gain any traction.