Senate Majority Leader Harry Reid, D-Nev., revived his suggestion that Mitt Romney has avoided paying income taxes in recent years.

“For all we know, Mitt Romney could be one of those who have paid no federal income tax,” Reid said on the Senate Floor this morning. “Thousands of families making more than a million dollars a year pay nothing in federal income taxes. Is Mitt Romney among those?”

Romney’s 2010 tax return shows that he paid an effective income tax rate of 13.9 percent. Romney says he’s never paid less than 13 percent in taxes.

But Reid, who was speaking apropos of Romney’s remarks about the “47 percent of Americans” who pay no income tax but receive government benefits, never misses an opportunity to accuse Romney of avoiding taxes.

The Nevada Democrat has claimed in recent months to have an anonymous source who told him that Romney paid no taxes for a decade. When pressed to provide evidence for that accusation, Reid grew irritated with the reporters who questioned him.

“I don’t think the burden should be on me,” Reid said on a conference call. “The burden should be on him. He’s the one I’ve alleged has not paid any taxes.”