Marquette poll: Leah Vukmir and Kevin Nicholson in a dead heat in GOP U.S. Senate primary

With less than a month to go before the primary, the Republican race for U.S. Senate is in a dead heat, according to Wednesday's Marquette University Law School poll.

State Sen. Leah Vukmir of Brookfield had 34% support and Delafield businessman Kevin Nicholson had 32%, well within the survey's 7% margin of error.

"I think it would certainly be fair to call it a toss-up race at this point," said poll director Charles Franklin.

Campaigning is expected to step up ahead of the Aug. 14 primary, with millions of dollars in TV ads set to blanket the airwaves.

The candidates still remain relatively unknown among GOP primary voters.

"Neither of them have become substantially any better known than they were, so there is still lots of uncertainty and 30% of Republican primary voters said they hadn't made up their mind," Franklin said.

Nicholson held a 9-point lead over Vukmir in a March Marquette poll and had a 5-point advantage last month.

"There has been a trend in three polls of narrowing in the race," Franklin said.

Vukmir campaign manager Jess Ward said: "The last two polls show that momentum has been with Leah ever since she earned the endorsement of the grassroots of the Republican Party of Wisconsin" and endorsements from House Speaker Paul Ryan, and U.S. Reps. Jim Sensenbrenner, Sean Duffy, Glenn Grothman and the NRA.

Nicholson's campaign also expressed confidence.

"We’ve known for months that this race would be tight," said Nicholson spokesperson Ronica Cleary. "Establishment and Washington Insiders are circling the wagons for Leah Vukmir and it’s not surprising that the ballot is close."

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The poll did not measure the two Republicans in head-to-head matchups with Democratic U.S. Sen. Tammy Baldwin, who was viewed favorably by 41% and unfavorably by 40%.

In head-to-head matchups last month, Baldwin led Nicholson by 50% to 39%, and Vukmir, 49% to 40%.

Trump's pick for the U.S. Supreme Court, Judge Brett Kavanaugh, was viewed favorably by 27% and unfavorably by 22%, with half those surveyed saying they didn't yet have an opinion.

The poll found public opinion on abortion has changed little since Marquette began polling in 2012.

Currently, 27% said abortion should be legal in all cases and 36% said it should be legal in most cases, while 18% said it should be illegal in most cases and 11% said it should be illegal in all cases.

Forty-two percent approved of the job Trump is doing as president, while 50% disapproved. Forty percent approved of the job Trump is doing with immigration while 53% disapproved.

Also Wednesday, former Gov. Tommy Thompson condemned the national Club for Growth ad push, which includes $2 million in new TV buys, most aimed at Vukmir.

In 2012, Thompson fought a bitter primary campaign against businessman Eric Hovde and emerged victorious but wounded politically. Club for Growth, which backed Mark Neumann in the primary, advertised against Thompson and Hovde.

Thompson lost in the general election to Baldwin.

“The national Club for Growth is at it again,” Thompson said in a statement issued through the Vukmir campaign.

"I won the 2012 GOP primary for U.S. Senate despite Club for Growth’s attacks," Thompson said. "Worse yet, the national Club for Growth never offered any help to my campaign in the general election, which gave Tammy Baldwin a huge cash advantage.

"I condemned the Club’s attacks in the GOP primary in 2012 and now in the 2018 primary. They are wasting precious resources that would be better used in the general election to elect a conservative to the U.S. Senate from Wisconsin.”

Club for Growth responded to Thompson in a series of tweets saying that his advice was not needed.

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