Senate Democratic leader Harry Reid has acted quickly to enliven the dog days of August, when Americans' attention begins to stray from politics, by charging that multimillionaire GOP candidate Mitt Romney paid no taxes, presumably income taxes, for 10 years.

The source for this is said to be someone with some association with Bain Capital, Romney's old firm, but Reid won't identify the source or offer any proof that the charge is true. Nonetheless, he repeated the accusation on the Senate floor.

Romney and advisers must have seen something like this coming when he decided not to release his tax returns. He did for one year, 2010, and they show he paid a very attractive rate of 13.9 percent on an income of $21.6 million.

It's good being Mitt Romney, maybe too good. His reason for not releasing more tax information is that Democrats will root around in the returns and use the information against him.

That immediately raises the question: What's in there that he doesn't want us to know about? We know about a tax loss of $77,000 for Ann Romney's horse. We know about the planned $12 million expansion of his La Jolla beach house with the elevators in the four-car garage. We're tough. We can take it.

In the friendly confines of the Fox News Channel, Romney said, "It's untrue, dishonest and inaccurate. So I'm looking forward to have Harry reveal his sources and we'll probably find out it's the White House." So far, this has been a remarkably fact-free discussion. If Reid offered no proof of his assertion, neither did Romney. If Reid is making McCarthy-like charges of borderline dishonesty, we voters would like proof. Even more we'd like proof that the White House was behind it.

But Obama press secretary Jay Carney did his best to distance the White House from the controversy: "You can talk to Sen. Reid. I'm sure he'll address this issue if you ask him. He certainly speaks for himself."

One who did speak for himself was Republican National Committee chairman Reince Priebus, who elevated the political dialogue by calling Reid "a dirty liar." Maybe so, but there's only one way to prove it. Release the tax returns. Either Reid or Priebus will come out of this looking really bad. As for Romney, it will only prove what we already know: He's a very rich guy with great tax lawyers.

Dale McFeatters is a senior writer for the Scripps Howard News Service.

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