Frank Bruni gave the best explanation for why Donald Trump is beating the dead birther horse again. “Trump’s motivations are surely less racist than narcissistic, even entrepreneurial,” he wrote. “For him attention is attention and ratings are ratings, no matter how repulsively drummed up.” So true. You need only read my interview with him from last year or watch a Darrell Hammond impersonation on  “Saturday Night Live” to know it to be true.

But when pressed for a reason why he would associate himself with someone so openly embracing a proven lie — and a racist one, at that — Mitt Romney could only muster this inadequate response. “You know I don’t agree with all the people who support me, and my guess is they don’t all agree with everything I believe in,” he told reporters on his campaign plane on yesterday. “But I need to get 50.1 percent or more, and I’m appreciative to have the help of a lot of good people.”

This explanation has the same feel as the one Romney gave last year during a debate to swat back accusations that he hired undocumented workers. “So we went to the company, and we said, ‘Look, you can’t have any illegals working on our property. I’m running for office, for Pete’s sake! I can’t have illegals!’ ” The propriety of hiring illegal workers didn’t seem to bother the former governor as much as the impact of doing so would have on his political ambitions.

At what price does Romney put political ambition aside to do or say the right thing? To stand up to the absurdity in his own party? To shut down the ignorant talk of his prominent supporters? Trump is hosting a fundraiser in Las Vegas for Romney this afternoon with a goal of $2 million. So Romney’s price is well north of that, it would seem.