AUGUSTA — Three organizations tied to a southern Maine casino referendum under investigation by state officials have missed another deadline for reporting their financial activity to campaign regulators.

Political action committees and ballot question committees were supposed to file reports outlining recent campaign fundraising and expenditures with the Maine Ethics Commission by day’s end on Monday. But three of the four committees funding a controversial York County casino referendum had yet to file updated reports as of Tuesday afternoon, despite the already intense scrutiny of the campaign’s financial record-keeping.

Last Friday, the five-member Ethics Commission agreed to delay an investigation into the ballot initiative’s compliance with Maine’s campaign finance laws and granted Lisa Scott additional time to provide banking records and other documents. The commission is investigating the sources of the more than $4 million that has flowed to the campaign so far, nearly all of it apparently from either Scott or her brother, international gambling entrepreneur Shawn Scott, or other associates.

Lisa Scott is listed as the treasurer for the three organizations that failed to file updated reports: International Development Concepts LLC, Lisa Scott and Miami Development Concepts LLC. The fourth ballot campaign committee on which Scott serves as an officer, Horseracing Jobs Fairness, reported a $7,000 contribution from her and $10,560 in expenditures between April 1 and June 30 but ended the reporting period with nearly $700,000 in “cash on hand.”

Neither Scott nor her attorney, Bruce Merrill, responded to a request for comment Tuesday afternoon.

Late filings can result in financial penalties, depending on the circumstances. Penalties also accrue for each day a filing is late and depend on how much money changed hands during the reporting period.

“It all depends on whether there was financial activity during the period,” said Jonathan Wayne, executive director of the Maine Ethics Commission. “Maybe there was no financial activity, in which case there would be zero penalty.”

The York County casino campaign has been embroiled in controversy almost from the start. The organizations behind the campaign spent more than $4 million to collect the signatures needed to qualify for the ballot, but that process was marred by complaints of aggressive or deceptive signature gatherers, questionable record-keeping and unpaid bills. The Maine Secretary of State’s Office invalidated more than 55,000 signatures last year, forcing the campaign to hit the streets again with paid petition circulators.

Last month, the ethics commission voted to investigate the campaign’s finances and to subpoena financial records from the campaigns, although Scott’s attorney walked out of the room without accepting the subpoenas.

Horseracing Jobs Fairness initially listed Lisa Scott, who lives in Miami, as the sole donor to the ballot initiative. But amended disclosure filings, ordered by the ethics commission, show that she received all of that money via loans from two entities, Capital Seven LLC of Las Vegas, which was at least formerly owned by her brother Shawn Scott, and Regent Able Associate Co. of Tokyo. The source of those funds was not disclosed in earlier financial reports.

Shawn Scott is a controversial figure who has become wealthy by often winning approval for gambling facilities and then cashing in by selling those rights to others. In 2003, he bankrolled the successful ballot initiative that authorized Maine’s first gambling facility in Bangor. He then quickly sold the rights to build the facility to Penn National, which still operates what is now known as Hollywood Casino. The proposed York County casino referendum is written in such a restrictive way that it would only allow Scott or his associates to build the facility, although there is speculation that he would once again look to sell those rights.

The campaign has also faced stiff criticism from lawmakers, who were considering ways to potentially block the referendum. But the law only gives the Legislature two options when presented with citizen’s initiatives that have gathered enough signatures from registered voters to qualify for the ballot: either approve the question outright, or allow voters to make a decision.

On Thursday, lawmakers will likely vote to send the ballot initiative to voters this November. But Rep. Louis Luchini, an Ellsworth Democrat who co-chairs the Legislature’s Veterans and Legal Affairs Committee that oversees election policy issues, said this week’s missed filings merely underscored his concerns about the campaign.

“To me, that shows they don’t really care about Maine’s laws,” Luchini said. “You can add this to the violations of Maine law that they have now.”

While Luchini acknowledged that late filings do happen, he expressed little sympathy or patience for the casino campaign.

“When you’re under an Ethics Commission investigation for improper filings (of financial reports), it seems you would at least make an effort to do it right going forward,” Luchini said.