Why Is Donald Trump Polling So Well?

National Journal explores this question, which has most sane human beings scratching their heads. This assessment, from a Democrat's perspective, struck me as being pretty close to right:

"He obviously benefits from his celebrity, but I think more to the point, there is no question that there is a segment of the Republican electorate that is strongly anti-immigrant and there is an overlapping piece of the Republican electorate that is anti-politician," says Geoff Garin, the president of the Democratic polling firm Hart Research. "Donald Trump appeals to those voters, and not in the most sophisticated way possible, but in the loudest way possible."

NJ goes on with a hopeful note:

But with so many qualified Republican presidential contenders out there, Trump's rise is not expected to last. Several pollsters consulted for the story say the recent bump may reflect the entrepreneur's high name ID more than it shows genuine voter support. And at a time when the Republican field is so fractured, with more than a dozen candidates in the race, Trump's low, double-digit poll numbers are enough to fling him toward the top. If he cannot expand his base, though, he's expected to fizzle out fast.

Trump's biggest impact may be the result of sucking up media oxygen – this will mostly impact the bottom feeders of the Republican field. If so, bad news, Bobby Jindal.