State Republicans say Franken, who was expected to pose a strong challenge to incumbent Republican Sen. Norm Coleman in the November election, is at fault. 

“Al Franken’s business activities must have a full, and complete public airing if he is to retain any credibility as a candidate for public office,” Ron Carey, chairman of the Republican Party of Minnesota, said in a statement.

Franken told the Minneapolis Star Tribune that errors by his New York accountant led him to overpay $49,253 taxes to New York state and Minnesota where he lived between 2003 and 2006, while not paying $53,404 in taxes to 17 states where he earned money for appearances and speeches.

The $70,000 is an estimation of what he owes, Franken said.

He and his wife, Franni, “believe in paying state and federal taxes on all our income,” Franken told the newspaper.

Carey said in a statement that Franken signed a disclosure statement showing he was aware of earning money in California and elsewhere.

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Photo credit: Reuters/Eric Miller (Al Franken speaks at rally in March)