Additional reporting by Yoav Gonen

Mayor Bill de Blasio used a political action committee to pay for presidential polling ahead of his short-lived White House run — potentially running afoul of contribution limits, according to the Federal Election Commission.

In a letter to the mayor’s Fairness PAC dated Sunday, a federal election official noted the $123,000 contribution from de Blasio 2020 wasn’t paid back in the alloted 30-day timeframe, exceeding a $5,000 annual limit.

De Blasio filed paperwork for his longshot White House run May 16, records show, putting the June 30 payment outside of the 30-day grace period.

The Fairness PAC, launched last year to help progressive Democrats running for office around the nation, will have to refund the “excessive amount” — unless the PAC is able to satisfactorily explain the payment in an amended report by late December.

The letter warned of possible “further legal action regarding the acceptance of an excessive contribution.”

The FEC sent a letter to Mayor Bill de Blasio’s Fairness PAC about a $123,000 donation from his presidential campaign. Credit: Federal Election Commission

The FEC’s review of de Blasio’s PAC echoed a July story THE CITY that noted the unusual $123,000 contribution.

Jon Paul Lupo, the former de Blasio 2020 campaign treasurer who runs the Fairness PAC, downplayed the FEC’s missive.

“Today’s letter about a payment that was properly reported four months ago by both Fairness PAC and de Blasio 2020 is neither new, nor conclusive. We will continue to work with the FEC on any pending issues about reimbursement timing,” he said in a statement.

Lupo did not say whether the contribution would be reimbursed.

Latest FEC Letter

The FEC letter made public Monday marked the second sent to the mayor over his unorthodox fundraising tactics, which used separate state and federal political action committees to help fuel his presidential ambitions. The strategy shielded some spending and donations amid strictly regulated federal rules.

In late September, just as de Blasio called off his White House run, the FEC inquired about a $52,852 debt to his state PAC, noting that contributions over $5,000 are prohibited.

The tangled web of money and donors — some of them with pending business before New York City government — prompted at least two complaints to the FEC. Both contended de Blasio’s presidential campaign broke federal campaign finance rules by failing to report tens of thousands of dollars in donations and expenses to federal regulators.

The $123,000 contribution was a focal point in the Washington-based Campaign Legal Center’s complaint, which cited reporting by THE CITY and POLITICO NY.

“By de Blasio 2020 failing to timely reimburse Fairness PAC for six figures in testing the waters expenses, the PAC made, and the de Blasio campaign accepted, excess contributions,” said Brendan Fischer, director of the federal reform program at the campaign-finance watchdog group.

Along with the federal Fairness PAC, the mayor also launched a state PAC with a similar name — NY Fairness PAC — to help New York Democrats. But the pair of committees wound up mostly aiding de Blasio, records show.

De Blasio campaign officials acknowledged in July that the federal Fairness PAC shouldn’t have paid for polling related to the mayor’s White House run. The money was reimbursed and reflected in the FEC filings.

Even after dropping out of the race, de Blasio said he would keep raising money for the federal Fairness PAC and traveling to support candidates across the country.

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