Wisconsin Gov. Scott Walker got some good news on Thursday, as the state Supreme Court issued a 5-2 ruling upholding the defining act of his term as governor, a sweeping 2011 law that all but eliminates collective bargaining for most public employees.

Walker is still waiting for the outcome of another legal case, a state investigation into his campaign's alleged illegal coordination with outside groups who spent heavily on his 2012 recall election. But his real concern these days is his reelection campaign, where polls have him tied with his Democratic challenger, Mary Burke. And if there’s any doubt that these polls are spooking Walker, consider the tack this conservative icon has started to take of late: attacking Burke with the rhetoric of a trade-bashing, tax-hiking liberal.

Burke is a former executive at Trek Bicycles, the big Wisconsin-based bike manufacturer founded by her father, and frequently invokes her business experience on the campaign trail. In response, Walker has started going after Burke with attacks borrowed straight from the playbook that Democrats have used against any number of Republican businessmen-candidates over the years, most notably against Mitt Romney in 2012. Walker has launched two ads hitting Burke for Trek’s outsourcing much of its manufacturing overseas. One ad shows small children being read a bedtime story about Burke sending jobs to China: “Mary, Mary, quite contrary, how does your fortune grow? By making millions of dollars . . . sending jobs overseas that could have been done in Wisconsin . . . to countries where women and children might work up to 12 hours a day, earning only two dollars an hour.”

Another one includes images of wan, underfed young Asian women, meant to represent the workers that Trek is underpaying in China. It concludes: “Mary Burke: Job creator? Not so much.” A website run by the Wisconsin Republican Party goes so far as to brand Burke a “one-percenter” and hits her for having worked for McKinsey, “a global consulting firm known for its outsourcing expertise.”

This is surprising stuff coming from a Republican who throughout his career has fashioned himself as a pro-business conservative willing to stand firm against liberals making cheap populist appeals. And Walker was called on it by one of his biggest boosters, the Wall Street Journal editorial page, where Allysia Finley chided him, hard: