WASHINGTON — During the 2012 presidential campaign, Harry Reid claimed to have intimate knowledge of what was secretly inside Republican presidential nominee Mitt Romney’s tax returns.

As President Obama’s campaign slammed Romney nearly every day for not releasing more tax returns, the Senate majority leader repeatedly made the unsubstantiated claim that, at one point in his life, Romney hadn’t paid taxes for almost a decade.

He even did so from the floor of the U.S. Senate.

“The word’s out that he hasn’t paid any taxes for 10 years,” the Nevada Democrat claimed on the floor in August. “Let him prove that he has paid taxes, because he hasn’t.”

It made big news at the time, but Reid’s old accusations are popping back up now that it’s been revealed that the IRS has been targeting conservative groups and in some cases, reportedly leaking their tax information.

Knowing that, could someone at the IRS have leaked Romney’s tax information to Reid? At the time, Reid claimed he learned of Romney’s tax background from someone who had once been an investor in Romney’s firm, though he wouldn’t say who.

Since the new IRS scandal broke, Republicans have found the question of who Reid got his information from — and from where — intriguing.

“We all wondered how Harry Reid had Mitt Romney’s taxes,” Republican National Committee spokeswoman Kirsten Kukowski told The Daily Caller. “The question is, will he call for a full investigation into the IRS?”

On Tuesday, Reid took a hard line against the IRS. “What the IRS did, of course, was inexcusable,” he said.

After this story was published Thursday, Reid spokesman Adam Jentleson told TheDC: “The answer to your question is no, the IRS did not leak Romney’s tax returns to Senator Reid.”

Here’s how Reid’s accusations went down last year: In an interview with The Huffington Post, Reid claimed he had been called by someone who had invested in Romney’s former firm, Bain Capital. That person said Romney didn’t pay taxes for 10 years.

“He didn’t pay taxes for 10 years! Now, do I know that that’s true? Well, I’m not certain,” Reid told the liberal news outlet. “But obviously he can’t release those tax returns. How would it look?”

Romney’s campaign denied Reid’s accusations, eventually releasing a summary of the former Massachusetts governor’s taxes that — according to Romney staffers — showed he paid taxes over the last 20 years.

But Reid continued to argue that Romney’s tax returns included something that the Republican didn’t want everyone to see.

“He’s hiding something,” Reid said on a conference call. “He’s hiding something! It is so evident he’s hiding something!”

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