Trump, and his Wallet, Are Untested

Republicans and even Donald Trump supporters might figure the time has come to pull out the stops and challenge the Trump steamroller, especially after Friday’s bizarre Chris Christie endorsement. Somebody ought to spend a very large amount of money to blanket the airwaves with negative Donald Trump ads, and not just to test whether Trump fans can withstand withering exposure to their man’s contradictions, lies and peccadilloes.

Also needing to be tested is whether Mr. Trump himself can stand it, and perhaps as important,...