The city Campaign Finance Board is probing a $1.1 million payment Mayor Bloomberg’s campaign made in 2009 that was largely ripped off by a political operative, who was tried and convicted last year.

The board will hold a hearing today on a complaint against the campaign’s “pre-election payments to the Independence Party.”

The complaint — which spokesman Eric Friedman would not discuss ahead of the hearing — could result in a fine to the billionaire mayor’s self-financed 2009 re-election bid.

The case involved Bloomberg giving $1.1 million to the state Independence Party, which then funneled $750,000 to Republican operative John Haggerty, who told the mayor he was spending the money on an Election Day voting-security operation.

Haggerty was convicted of grand larceny and money laundering in December and sentenced to 1 1/3 to 4 years in prison.