Whoever said all publicity is good publicity is now retracting the statement, as Donald Trump's self-destruction tour continues.

Trump's Mexican-immigrant-bashing entry into the GOP presidential race has backfired. He has made himself a human piñata, and not just the Donald Trump piñatas doing brisk business in Mexico.

His rant against Mexicans ("They are bringing drugs. They are bringing crime. They're rapists. . . .") has led NBC Universal, Macy's, Univision and other corporations to turn Trump's signature line ("You're fired!") on him. Of course, like an obnoxious, dumped boyfriend, he claims he's doing the dumping. NYC is also reviewing its contracts with him.

Still, Trump insists he's a brilliant businessman -- so brilliant that he's the only person running for president who is losing tons of money by doing so.

The case of an immigrant here illegally who fatally shot a woman in San Francisco may give Trump some traction on his idea to "build a great, great wall on our Southern border and make Mexico pay for it." But how exactly would he accomplish that? Restart the Mexican-American War?

While Trump's popularity has risen among some Republicans since his bombastic remarks, many believe he has zero chance of winning a national election. Trump as U.S. president? Maybe president of the Hair Club for Men. While he runs to promote his brand, it looks more and more like he's destroying it.

Meanwhile, Trump has moved up to second place in Republican polls. For a party trying to recruit Latino voters, he is a nightmare. How do you reach out to Latinos when one of your leading candidates is insulting and demonizing them?

But the Republican Party should collectively look in the mirror. The GOP's mockery and rejection of any reasonable immigration bill is a theme that Trump merely picked up and ran with, in its crudest form.

As the damage to his empire builds, will he drop out, or figure he has nothing left to lose and stay in the race?

With the first debate a month away, the GOP is in panic mode. Its overflowing clown car of candidates has a wild-card passenger elbowing his way to the driver's seat. And the hopefuls realize Trump can take them over the cliff with him.

Playwright Mike Vogel blogs at newyorkgritty.net.