Former Fund-Raiser for Grimm Pleads Guilty to Visa Fraud A former fund-raiser for Representative Michael G. Grimm, whose campaign finances are under investigation by federal prosecutors, pleaded guilty on Friday to visa fraud. The former fund-raiser, Ofer Biton, an Israeli immigrant who helped direct hundreds of thousands of dollars from supporters of a revered rabbi to Mr. Grimm's campaign before his election to Congress in 2010, was arrested last August and charged with lying on his visa application. Followers of the rabbi, Yoshiyahu Pinto, have said in interviews that Mr. Grimm or Mr. Biton told them that the campaign would find a way to accept donations that were over the legal limit, were given in cash or were given by foreigners who did not have permanent resident status. Congressional campaigns are not allowed to accept cash donations of more than $100 and foreigners without resident status are barred by law from donating to political campaigns. At the time of Mr. Biton's arrest, lawyers not involved in the case said that the charges appeared to have been meant to persuade him to cooperate with the authorities in the investigation of Mr. Grimm, a Staten Island Republican, who has not been charged with any wrongdoing. A spokeswoman for Mr. Grimm, Carol Danko, said that "the visa issues had nothing to do with Congressman Grimm." Prosecutors said last September that they expected to charge Mr. Biton with extortion and money laundering, but no additional charges ever materialized. In Federal District Court in Brooklyn on Friday, Mr. Biton, 40, was barely audible as he told the judge, Roslynn R. Mauskopf, that he had lied about the source of $400,000 that he claimed to have put into a new business that could have made him eligible for a permanent visa. "I know it was wrong," Mr. Biton said.