Some Democrats and Democratic-leaning incumbents, meanwhile, seem to be rooting strategically for Trump. According to many pundits, Trump would be the weakest candidate against Clinton or Sanders, and for that reason some Democrats hope he wins the nomination. Some may even cast a mischievous vote for him on Tuesday, seeking to help the eventual Democratic nominee.

That’s playing with fire. Just remember how few pundits believed Trump would ever make it this far.

The best way to stop Trump is to stop Trump now. Thanks to his landslide victories in New Hampshire and South Carolina against divided fields, that’s already an uphill battle. But as the race turns to Massachusetts, the answer to John F. Kennedy’s question — “ask what you can do for your country” — has rarely been clearer: unenrolled voters should pull a Republican ballot and vote for John Kasich because it’s a vote against Donald Trump.