One Number Shows Why Donald Trump Is Making a Very Risky Gamble in Wisconsin

Mere hours after Scott Walker endorsed Texas Sen. Ted Cruz for president, Republican presidential frontrunner Donald Trump ripped into the Wisconsin governor Tuesday, homing in on a target typically attacked by liberal Democrats.

"He's not doing a great job," Trump said in Janesville, Wisconsin, ticking off the state's unemployment figures, budget deficit and food stamp recipients — reprising some of the same criticism he leveled during Walker's short-lived presidential bid last year.

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With Wisconsin's budget woes forcing deep cuts in education programs and the state reeling from a divisive debate over Walker's decision to sign legislation last year further gutting labor union power, Trump's target is a seemingly soft one.

In a Marquette University poll conducted in February, the governor's approval rating stood at just 39%, with 55% disapproving of his job performance.

But another figure underscores the risky gamble Trump is making in inveighing so heavily against Walker: 85%.

That's the percentage of Republicans who approved of Walker's job performance in the Marquette poll, and Walker's overwhelmingly popularity with GOP voters could prove a major hurdle for Trump — and a boon to Cruz — ahead of Wisconsin's April 5 primary.

Of course, Trump's withering attacks on his GOP opponents have eviscerated everyone from low-polling rivals like Rick Perry and Lindsey Graham to erstwhile juggernauts Jeb Bush and Marco Rubio. It's not inconceivable that, in targeting Walker, Trump may force the governor's numbers downward among Republican voters — and hitting Walker on unemployment, budget deficits and food stamps may well undercut his appeal among fiscal conservatives.

But Trump isn't jabbing at Walker exclusively from the right. In an interview with Illinois radio's The Michael Koolidge Show on Tuesday, Trump slammed the governor for pursuing budget cuts instead of tax increases, arguing that revenue hikes could have forestalled slashes to education and infrastructure programs.

"There's a $2.2 billion deficit and the schools were going begging and everything was going begging because he didn't want to raise taxes because he was going to run for president," Trump said in remarks quoted by the Guardian. "So instead of raising taxes, he cut back on schools, he cut back on highways, he cut back on a lot of things."

Deviating from conservative orthodoxy, however, hasn't prevented Trump from building a massive delegate lead over his GOP rivals, and it remains unclear whether Wisconsin Republicans are hungrier for a candidate who fashions himself a model of conservative purity, à la Cruz, or one whose pugnacious attitude channels their anti-establishment rage.

At any rate, Trump has little margin for error. Polls show the race in Wisconsin is a pure toss-up, with the RealClearPolitics average finding Cruz at 33%, Trump at 32% and Gov. John Kasich of Ohio at 23%.