People here at Ted Cruz’s campaign headquarters are meticulously preparing to win a contested convention, if there is one. Because Donald Trump is a low-energy fellow, Cruz will be positioned to trounce him in Cleveland, where Trump’s slide toward earned oblivion would accelerate during a second ballot.

Wisconsin has propelled Trump, a virtuoso of contempt, toward joining those he most despises: “losers.” In the 1992 general election, Ross Perot, a Trump precursor, won 21.5 percent of Wisconsin’s vote, above the 18.9 percent he won nationally. Wisconsin’s populist tradition is persistent and indiscriminate enough to encompass Robert La Follette and Joseph McCarthy. And evangelical Christians are less important in Wisconsin than in contiguous Iowa. Nevertheless, temperate Wisconsin rejected Trump, partly for the reason that one of his weakest performances so far was in the reddest state, Utah, where conservative Mormons flinched from his luridness. His act — ignorance slathered with a congealed gravy of arrogance — has become stale.

If, as seemed probable a month ago, Trump had won Wisconsin, he would have been well-positioned to win a first-ballot convention victory. Now he is up against things to which he is averse: facts. For months Cruz’s national operation has been courting all convention delegates, including Trump’s. Cruz aims to make a third ballot decisive, or unnecessary.