Former Wisconsin Sen. Ross Feingold leads incumbent Republican Sen. Ron Johnson 47 percent to 41 percent among likely voters in the Badger State, according to the latest Marquette Law School poll.

Feingold, a Democrat, held this seat for three terms before losing to Johnson in 2010.

In late August, the same survey gave Feingold a more modest 3-point edge, 48 percent to 45 percent. The current RealClearPolitics average of polls from Aug. 27 to Sept. 20 has Feingold ahead by 9.7 points.

Eight percent of voters in the Marquette poll said they didn’t have a preference.

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