Rep. Ron Paul, R-Texas, speaks at a rally at the University of South Florida Sun Dome on the sidelines of the Republican National Convention in Tampa, Fla., on Sunday, Aug. 26, 2012. (Charles Dharapak/AP)

Texas Republican Rep. Ron Paul has been named one of the most corrupt members of Congress in a new report from the watchdog group Citizens for Responsibility and Ethics in Washington.

The report says Paul "double-billed" his travel expenses a number of times over the last decade, meaning he may have been reimbursed for the same flights both under his official allowance as congressman, and by either non-profit groups under his control or his campaign committee.

The revelation would be ironic in part because Paul made fiscal responsibility a central tenet of his 2012 presidential campaign. The congressman celebrated a major victory in July when his bill to audit the Federal Reserve for greater transparency passed the House.

Paul's possible double-billing has been in the public eye since Roll Call first reported it in February, but CREW says there is no evidence Paul has repaid the money since.

A request for comment from Paul's office was not immediately returned.

One of the most troubling cases of the congressman's possible double-billing revolves around reimbursements he received for flights from both his official allowance and the libertarian group the Liberty Committee. At that time, the Liberty Committee's finances were overseen by a relative of the Paul family.

"It's extremely disappointing," Liberty Committee President David James told Whispers of the double-billing.

James says he first noticed a red flag in 2004, after the committee asked Paul for copies of his travel tickets, and the congressman did not provide them. Paul stopped billing the committee shortly after they asked for the tickets, according to James. By 2005, James says he was aware of possible double-billing. But it wasn't until the Roll Call story that he saw how far the problem extended.

The committee conducted its own audit of Paul's finances shortly after the story, and found that 60 percent of the travel Paul had billed to the committee had been doubled-billed.

"We have contacted Congressman Paul to look at the records and repay the amount," James told Whispers. "But our last communication was not even responded to."

James said the committee parted ways with the congressman in 2006 for "a number of reasons."

The committee has not, however, stopped vocally supporting Paul.

James called his policies "just what this country needs." "The message is great," said James. "It's the messenger that is the problem."

Update, 3:13 p.m.:

Paul’s office says it declines to comment on the CREW report, and referred Whispers back to the comment given to Roll Call in February.

At the time, Paul’s spokesman Jesse Benton denied the congressman was reimbursed multiple times for the same trips, saying "absolutely zero taxpayer funds were ever misused." Benton also said it was "possible that wholly inadvertent errors were made in a handful of instances.”

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