Donald J. Trump is the clear frontrunner for the Republican presidential nomination.

I’ll concede that much.

It’s interesting, though, to listen to other Republicans tear into him. It makes me wonder — not that I’m predicting it, given the wackiness of this campaign — whether the intraparty opponents will soften him up for the Democratic candidate who might face him this fall.

Marco Rubio blasts Trump for hiring illegal immigrants to build his hotels. He calls Trump a “con man.”

Ted Cruz accuses Trump of hiring foreign workers over American workers to work in his “world-class companies.”

Former GOP presidential nominee Mitt Romney challenges Trump to release his tax returns.

Lindsey Graham says his party has gone “bats*** crazy” by backing Trump.

It reminds me a bit of the 1988 Democratic primary campaign when Sen. Al Gore of Tennessee introduced the “Willie Horton” issue to voters, reminding them of how Massachusetts Gov. Michael Dukakis signed off on a furlough for a prison inmate who then went on a crime rampage. Republicans seized on that theme and beat Dukakis senseless with it during the fall campaign that year.

And so it goes.

Nothing about this campaign makes conventional sense.

It might be that all this piling on only will strengthen the Republican frontrunner.

It’s making me crazy, y’all.