Key Republicans accuse top Democrat of lying on Romney tax charge

U.S. Republican Presidential candidate Mitt Romney (2nd R) waves next to Governor Scott Walker (R), Representative Paul Ryan (2nd L), and RNC Chairman Reince Priebus (L) before speaking to a crowd at Monterey Mills in Janesville, Wisconsin, June 18, 2012.

WASHINGTON (Reuters) - The U.S. presidential campaign's war of words turned increasingly bitter on Sunday with two influential Republicans accusing the top Senate Democrat of lying when he said their party's presidential hopeful, Mitt Romney, had not paid income taxes for 10 years.

Reince Priebus, the Republican Party's national chairman, called Senate Majority Leader Harry Reid "a dirty liar" for his accusation, based on a source that Reid has not named.

"I'm not going to respond to a dirty liar who hasn't filed a single page of tax returns himself," Priebus said in an interview on the ABC News program "This Week."

Republican Senator Lindsey Graham called Reid's statement "out of bounds" and said "I think he is lying about his statement of knowing something about Romney." Graham spoke on CNN's "State of the Union." "I think he's making things up."

Romney, a wealthy former private-equity executive who is the presumptive Republican nominee in the November 6 election, has released his 2010 tax return and said he will release the 2011 when it is completed. He has strongly denied Reid's claim, made on the Senate floor on Thursday.

"Let me also say categorically: I have paid taxes every year. A lot of taxes," Romney said during a campaign stop on Friday in Las Vegas, Nevada, Reid's home state. He called on Reid to "put up or shut up" by disclosing his source.

Priebus' role as chairman of the Republican National Committee is to develop and promote the Republican political platform. He coordinates fundraising and strategy for battling Democratic President Barack Obama's re-election bid as well as congressional elections.

REID RESPONDS

Reid stood his ground on Sunday, saying through a spokesman that the issue would not go away until Romney "decides to be straight with the American people and release his tax returns."

"As Senator Reid has said, an extremely credible source informed him that Mitt Romney did not pay taxes for 10 years," Adam Jentleson, his spokesman, said in an emailed statement.

Jentleson said the 2010 return Romney released showed that he "uses secret offshore accounts in places like Switzerland and the Cayman Islands to avoid paying U.S. taxes."

Romney has said the source cited by Reid may be within the White House or Obama's re-election campaign, which has frequently called on Romney to release more than the two years' worth of tax information that he is making public.

The Democratic National Committee chair, Representative Debbie Wasserman Schultz, said Romney could clear up the matter by releasing what she said were 23 years' of tax returns that he gave to 2008 Republican presidential nominee John McCain when he was being vetted as a potential running mate.

Financial data released by Romney in January showed he had paid an effective tax rate of 13.9 percent in 2010 mostly from capital gains on investments, well below the 35 percent top tax rate for wages.

Wasserman Schultz faulted the Republican hopeful for failing to respond to a reporter's question on whether he had ever paid a rate below 13.9 percent. At the time, Romney said he would check and provide an answer.

"I'm glad I wasn't holding my breath waiting for Mitt Romney to get back to us on answering that question," she said on ABC before Priebus spoke, "because he still hasn't responded whether he's paid a lower tax rate."

(Editing by Jackie Frank and Vicki Allen)