How Majority Rule Might Have Stopped Donald Trump

In the early contests, Mr. Trump attracted less than 50 percent of the vote (in Arkansas he got only 33 percent); a majority of voters rejected him. But he faced more than one opponent every time, so that the non-Trump vote was split. That implies he could well have been defeated in most (given his extreme views on many subjects) had the opposition coalesced around one of his leading rivals.

.. Using the current system, however, the plurality winner would be Mr. Trump — with 40 percent support. Yet he would surely be an odd choice, since he would be defeated not only by Mr. Kasich but also by Mr. Cruz (in both cases by 60 percent to 40 percent) in pairwise comparisons. Note also that Mr. Kasich, the majority winner, would come in a poor third under the current system, with only 25 percent support.\

.. Kenneth Arrow’s famous “impossibility theorem” demonstrates that there is no perfect voting system, and majority rule is no exception.