The Republican Party was born in Wisconsin in 1854, first in a little white schoolhouse in Ripon and then at a state convention in Madison.  

And 162 years later, the calm deliberation of Wisconsin primary voters may have saved the modern Republican Party.  

For the second time in three weeks, Donald Trump endured a double-digit thumping in a midwestern state that shimmers in GOP history. Ohio — which produced five of the first nine Republican presidents — stung Trump on March 15 by opting for Gov. John Kasich.  

These two firewall-for-sanity states awarded Trump just six out of 108 delegates at stake. As a result, the bilious billionaire will probably fall short of a 1,237-vote majority at the end of the primaries in two months.  

A little-noticed factor contributed to Ted Cruz’s Wisconsin sweep. For the first time since Iowa (which Cruz won narrowly), Republican voters had a chance to contemplate the chilling reality of President Donald J. Trump without being whipsawed by the constant barrage of other primary results.  

GOP chairman Reince Priebus deliberately encouraged the clustering of 30 primaries and caucuses in March on the dubious theory that a foreshortened presidential race would produce a consensus nominee.  

Instead, Priebus earned a place of honor among political leaders who arrogantly believed that they could outsmart the Law of Unintended Consequences. Democracy without time for deliberation produces chaos — and a delegate lead for Trump, a candidate who embodies the authoritarian temptation in 21st century garb.  

But Wisconsin voters had two weeks to make up their minds — and this slower pace encouraged strategic voting.  

Anti-Trump voters decided that the ultraconservative Cruz had a better chance of winning than the far more moderate Kasich. As a result Cruz easily won college-educated voters, a group that had belonged to Kasich in both the Michigan and Ohio primaries.  

The GOP calendar now offers another pause for reflection with nearly two weeks until the April 19 New York primary. That 12-day gap (a lifetime in politics) is probably why it is a mistake to over-interpret current polls that show Trump running around 50 percent in New York.  

The easiest way to clear a room or to stop a reader mid-column is to launch into a detailed description of the GOP’s delegate selection rules. So to simplify: The 92 delegates at stake in the New York primary are awarded proportionally unless a candidate achieves a majority statewide (garnering 11 delegates) or in individual congressional districts (81 delegates at stake).  

In practice, this means that the smartest ploy is for the feuding Cruz and Kasich camps to do their own thing in New York in the hopes that they can collectively hold Trump under 50 percent almost everywhere. For all the glib talk that Kasich is doomed after his dismal 14-percent showing in Wisconsin, the Ohio governor leads Cruz in most Empire State polls.  

So where does Wisconsin leave the Republicans?  

The results suggest that Trump can be stopped if the GOP establishment follows the advice that Margaret Thatcher gave George H.W. Bush during the run-up to the Gulf War: “This is no time to go wobbly, George.”  

Nominating Trump would spell disaster for the Republican Party in three separate ways.  

Trump’s shocking ignorance of policy and government (not knowing what the nuclear triad is), his disdain for democratic norms (his wink-and-nod encouragement of violence at his rallies) and his out-of-control egomania (do we really need examples?) all suggest that he should never be entrusted with the nuclear codes.  

The former reality TV host’s I-have-a-scheme issue proclamations constantly overturn GOP orthodoxy from his isolationist America First foreign policy to his angry repudiation of free trade. And it is hard for any Republican — regardless of views — to listen to Trump on abortion and find even a glimmer of conviction or coherence.  

All current evidence suggests that Trump as GOP nominee would beat the modern record of Barry Goldwater (38 percent of the vote in 1964). According to the Wisconsin exit polls, 36 percent of GOP voters would not back Trump in a race with Hillary Clinton. For all the Trumpian anger and threats, simple arithmetic suggests that a candidate cannot win in November when 70 percent of women voters revile him.  

In short, if the Republicans select Trump, they would be committing suicide three different ways. They would abandon the nation by nominating an unqualified candidate, they would jeopardize principle and they would risk bringing down the entire ticket.  

But some Republicans leaders and elected officials cling to the fantasy that uniting around Trump — if he is just short of the nomination — is the only way to save the party from splitting apart. That is the political equivalent of staying in an abusive marriage for the sake of the children.  

Wisconsin voters have given mainstream Republicans a chance to wiggle out of their fatal embrace of Trump. It would be tragedy for both the GOP and the nation if they lack the courage to take it.  

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