Donald Trump, riding a wave of publicity off his vocal doubts about President Barack Obama’s birthplace, asserted Monday that he is the White House’s “worst nightmare.”

Donald Trump addresses the Conservative Political Action Conference (CPAC) in Washington on Feb. 10. (AP Photo/Alex Brandon)

Appearing on Fox News Channel’s chatty morning show “FOX and Friends,” the real estate magnate, reality television star and would-be GOP presidential candidate reacted to White House senior adviser David Plouffe’s dismissive reaction to Mr. Trump’s rise in Republican primary polling. Far from evincing fear of The Donald, Mr. Plouffe said, in effect, bring it on.

“I saw Donald Trump kind of rising in the polls. Given his behavior, and the spectacle of the last couple of weeks, I hope he keeps on rising,” Mr. Plouffe said on ABC’s “This Week.” “There’s zero chance that Donald Trump would ever be hired by the American people to do this job.”

But Mr. Trump comes from the “no publicity is bad publicity” school of public relations…