Ned Lamont's campaign filed a complaint with the Federal Election Commission on Monday, accusing Sen. Joe Lieberman of failing to account for $387,000 in petty cash his campaign spent days before the Democratic primary.

The Lieberman campaign has denied any wrongdoing.

"The public has a right to know how nearly $400,000 in cash was spread around the streets of Connecticut," said Lamont campaign co-chairman George Jepsen at a news conference.

Records must be kept of petty cash expenditures, Jepsen said.

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Lieberman spokeswoman Tammy Sun said Sunday, when the allegations first surfaced, that the cash was paid to field coordinators who then distributed money to workers who were canvassing. The payments to workers, many of them students, ranged from $50 to $100 per day, Sun added.

"Ned is starting to feel like he has nothing to lose and its increasingly clear that he'll now stop at nothing to win, including crazy charges of vote-buying and thuggery," Sun said in response to the complaint.

Lamont defeated Lieberman in the Democratic primary. Lieberman opted to run as an independent, and in the latest statewide poll, Lieberman had a 17 percentage point lead in the race with about two weeks remaining.

The Lamont camp cited at least 10 petty cash payments to volunteers from July 25 to Aug. 7, the day before the primary. The largest was $135,000 on Aug. 4. There was a $75,000 payment on Aug. 7.

The payments are listed in Lieberman's primary campaign spending report filed with the Federal Election Commission.

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