MADISON, Wis. — Comedian Sarah Silverman called Democratic U.S. Senate candidate Russ Feingold a “progressive rockstar” in a fundraising plea Wednesday, while Wisconsin Gov. Scott Walker planned to hit the campaign trail to help incumbent Republican Sen. Ron Johnson.

The action comes less than three weeks before Election Day and the day after Johnson and Feingold squared off in their second and final debate. Their race, a rematch of the 2010 contest Johnson won, is one of the most closely watched Senate races in the country.

A new poll on the race was released Wednesday. The Monmouth University survey showed Feingold leading Johnson by 8 points. That comes on the heels of a St. Norbert University poll released Tuesday showing Feingold up by 12. A Marquette University Law School poll last week had the race about even.

The Monmouth poll of 403 likely Wisconsin voters was conducted by telephone from Saturday to Tuesday. It had a margin of error of plus or minus 4.9 points.

Feingold has never trailed in the Marquette poll, although it has shown the race tightening. Johnson’s campaign has expressed confidence that the race is close based on its internal polling data.

Walker will be campaigning with Johnson on Sunday as part of his promised focus on helping state candidates, not GOP presidential nominee Donald Trump. Walker, along with Wisconsin Republican Party Chairman Brad Courtney, planned to make stops in Eau Claire, Wausau, Green Bay and Waukesha. Details about the visits were still being finalized.

Hours before the latest poll showing Feingold ahead in the race, his campaign sent the fundraising email signed by the comedian Silverman. She is a Democrat and appeared at the party’s national convention in July.

Her message, where Silverman asks for as little as $5 to help Feingold, comes after a similar ask on behalf of Feingold by famed actor and director Robert Redford.

Silverman called Feingold “one of the very few totally righteous politicians who has always voted on the right side of history.” She didn’t cite examples, but Feingold was the only senator to vote against the Patriot Act.

He also voted for the Affordable Care Act, something Johnson has used to attack Feingold in the campaign and in both Senate debates. Feingold’s support for the law has also been the subject of television attack ads run against him.

Silverman noted Johnson’s support for Donald Trump and calls Johnson a “bought-and-paid-for Tea Party shill.”

Johnson campaign spokesman Brian Reisinger noted the Monmouth poll had tightened since August and said that and other polls show that Johnson “has the momentum.”

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