Robert Mentzer

USA TODAY NETWORK-Wisconsin

Donald J. Trump is probably not going to win Wisconsin and everyone is wondering what that means.

Is it that having his campaign manager charged with battery against a female reporter, a thing that actually happened this week, was the actual last straw for Trump voters otherwise inured to outrageous behavior by the campaign? Is it that Wisconsin's conservative talk radio hosts, in pointed contrast to their nationally syndicated peers, have been forceful and unyielding anti-Trump voices? Is it that we polite, reserved Midwesterners are just immune to Trump's abrasive style?

Who knows. But multiple public opinion polls in the last few days have shown Texas Sen. Ted Cruz comfortably ahead of the blustering billionaire, set to pick up a bunch of delegates in Tuesday's primary. In particular, the data show Trump to be especially unpopular among Republicans in the state's reddest and most populous Republican counties: the crescent of suburbs around Milwaukee. The Marquette University Law School poll, which usually gets Wisconsin right, shows Trump with only 28 percent support from Republican voters in Milwaukee suburbs.

If those numbers hold, Trump is going to lose here. But in true Trumpian fashion, he won't lose without doing a bunch of damage to the state's Republican Party infrastructure.

That's because Trump's lines of support in Wisconsin reveal some regional fault lines that ought to be worrying Republicans. In the more rural north and the west of the state, he is winning, or at least he could win. On CNN on Thursday, Rep. Sean Duffy said he suspects his vast district, which extends from Wausau to Bayfield, will vote for Trump. Duffy earlier in the week told the Wall Street Journal that "There’s a number of people in my district who are quiet Trump supporters." A profile in political courage himself, Duffy, who previously endorsed Florida Sen. Marco Rubio, said he would remain neutral in this primary.

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As far as anyone can tell, Trump's first and only endorsement among Wisconsin state legislators came from James "Jimmy Boy" Edming of Glen Flora. Edming, who ran for state Senate in 2010, told the Wausau Daily Herald editorial board back then that his platform was "garage logic" and that everything he needed to know about legislating he'd learned from fixing old cars — making him sort of the perfect Trump-supporting politician. This week he told the Wall Street Journal not only that he would vote for Trump but also how the GOP's internal civil war is affecting him: "Now that I’m seeing that the Republicans are trying to tackle Donald Trump," he said, "the more I see on the news, the more pissed off I get."

The polls show nothing like this sort of Northwoods-vs.-Milwaukee split within Wisconsin's Democratic Party. Hillary Clinton edges out Bernie Sanders in Green Bay and suburban Milwaukee; Sanders beats Clinton in Madison, obviously, and in the north. But it's not a particularly stark divide, and it doesn't feel like much of a civil war even in comparison to the 2008 Democratic primary, which at the time felt quite heated but now seems like a bygone era of civility and substance.

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If the polls hold and Cruz wins most of Wisconsin's delegates on Tuesday, that will have serious consequences for the rest of the Republican nomination battle, and will increase the likelihood of a chaotic, contested GOP convention. That's exactly the outcome a lot of Republican leaders want, and as a national story it's seen as a sort of comeback by the GOP establishment.

But the Wisconsin Republican Party still has a lot of voters like Jimmy Boy Edming. And if Trump loses, and especially if he loses at the convention, they are going to see it as a Republicans "trying to tackle Donald Trump." In Wisconsin, they'll blame suburban Milwaukee, and they'll be right to. How mad will they be, and for how long? Mad enough to break with Wisconsin's Waukesha County-dominated Republican Party?

The election is Tuesday. The fallout from the chaos this election has sown has barely begun.

Robert Mentzer is central Wisconsin storytelling coach and a columnist for USA TODAY NETWORK-Wisconsin, which is where this piece first appeared. Follow him on Twitter @robertmentzer.

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