BELOIT, Wis. — Sen. Ron Johnson, R-Wis., wants to repeat his 2010 victory over Democratic former Sen. Russ Feingold using a modified version of the same playbook — but things are different now.

Despite being the incumbent and a committee chairman, the Republican businessman from Oshkosh hopes the same anti-Washington sentiment that propelled him past a relatively popular three-term senator as a political newcomer six years ago will secure him re-election in November.

Johnson's strategy hinges on painting an opponent who has been out of office for five-and-a-half years and still enjoys a reputation as a maverick lawmaker as a hypocritical insider instead. But the Republican must hold together voters who are both for and against GOP presidential nominee Donald Trump.

Trump's unpopularity in the Dairy State is the X-factor that could tear Johnson's carefully drafted playbook to shreds.

Feingold consistently maintains leads outside the margin of error and is still better known than the somewhat enigmatic 61-year-old millionaire Republican who made his fortune manufacturing plastics.

Johnson is running 4 points ahead of Trump and doing better with party loyalists. And although he trails Feingold in the money chase, he just had his best fundraising quarter yet. Moreoever, outside conservative super PACs are outspending liberal groups 4-to-1 in the state.

The race tightened in March — last August Feingold was up by 10 points — and hasn't really moved since. The latest Marquette University Law School poll had Feingold up 6 points.

"Not much has changed," Johnson campaign spokesman Brian Reisinger acknowledged. "But what's clear is Ron Johnson is an outsider running his own race. As Wisconsinites tune into this campaign, they'll remember Sen. Feingold is a career politician who doesn't know the first thing about creating jobs or keeping us safe; and after 34 years, they'll fire him again."

Democrats are doing everything they can to tie Johnson to Trump, who lost the Wisconsin presidential primary to Texas Sen. Ted Cruz.

"Ron Johnson is still standing with Donald Trump, even after the GOP presidential nominee's disgraceful attacks against a Gold Star family, and now he's turning to the Koch brothers for a bailout," a recent Democratic Senatorial Campaign Committee statement read, referring to Trump's spat with the Khan family and the billionaire industrialist brothers, Charles and David, who have spent hundreds of millions of dollars to elect Republican candidates.

In interviews with Wisconsin voters it was clear that the Johnson-Feingold contest had taken a back seat to the presidential contest and schism between Trump and House Speaker Paul Ryan, which culminated in Ryan's anti-climatic drubbing of a Trump-inspired primary challenger for his 1st District seat.

"It's one of those that it's going to come down to the last day that I'm going to decide," said Diane of Janesville, who didn't give her last name.

"That's a tough one," said Stan Milam of Beloit. "I have voted for Feingold before but last time voted for Johnson."

"I don't think anything has fundamentally transformed the race yet," Madison-based Democratic pollster Paul Maslin said. They've been at it for a year now but the poll numbers have remained essentially flat. "I think that's instructive about where the race sits and the advantage Feingold has had all along," Maslin said.

Marquette University poll director Charles Franklin said he found one development in his data.

Both Feingold's favorable rating rating, 44 percent, and unfavorable, 36 percent, numbers ticked up while Johnson's, at 34 percent to 32 percent, didn't move. Thirty-three percent of voters still had no opinion of Johnson.

"It's the first signal we've seen in a long time that some people are tuning into that race who haven't tuned in before," Franklin said.

The Wisconsin voters who shared their preference with the Washington Examiner were evenly split.

"I'm probably for anybody against Russ Feingold," John Hudson of Janesville said.

"It will be hard for me to support a Republican in the Senate," chimed in Beloit's Matthew Brown.

Feingold's steady lead does not by any means indicate Johnson is a sitting duck, cautioned Maslin, who does polling for the DSCC.

Feingold himself has repeatedly said he expects it to go down to the wire.

Both sides agree it will come down to turnout. But even Republicans admit that a Clinton blowout could hurt Johnson and other down-ballot Republican candidates in the state.

Wisconsin Republicans have one of the best ground games in the country. However, the state hasn't gone Republican in a presidential contest since 1984.

One Republican insider said Johnson should just ignore Trump.

"Johnson should just talk about what he can do and what believes in," the insider said. "And pretend that Donald Trump went down in his airplane and that this never, ever happened."