AUGUSTA — The Maine Ethics Commission voted 3-0 Wednesday to levy a $500 penalty against a political action committee run by Speaker of the House Sara Gideon, D-Freeport, for contributions it made in her name in 2016.

Gideon, widely considered the front-runner for her party’s nomination to challenge incumbent Republican U.S. Sen. Susan Collins, has previously admitted to the violations, saying they were a mistake made based on bad advice she was given at the time.

Republicans, however, have seized on the complaint as they seek to return Collins to office for a fifth term. Before Wednesday’s vote, the Republican National Senatorial Committee unleashed a new digital ad campaign against Gideon, drawing attention to the complaint and calling her a “straw donor,” one who intentionally makes contributions on behalf of another, unidentified person.

The complaint was filed by Edward Youngblood, a former state senator from Brewer, after he learned that the now-shuttered Gideon Leadership PAC reimbursed Gideon for two $250 donations she made to two other PACS in violation of state campaign finance regulations.

The commission’s staff recommended that the case against Gideon be dropped. Jonathan Wayne, the commission’s executive director, said that recommendation was based on several factors, including the fact that Gideon’s PAC disclosed the donations and the reimbursements, making no attempt to conceal the transfer of funds, that the dollar amounts involved were relatively low, that the activity was three years old and that the overall damage to the public from the violation was minimal.

Considering those factors, the commission, which was missing two of its five members, levied a penalty of just 10 percent of the maximum $5,000 fine prescribed by law. They noted that Gideon, who was the primary decision-maker for the PAC, did not attempt to hide the contributions or expenditures but did violate the letter of the state’s law – which prohibits making donations in another person’s name.

Youngblood said in an interview later that he did not believe the violations by Gideon or her PAC amounted to her being a straw donor.

One commission member, Meri Lowry, a Portland Democrat, recused herself from the proceedings Wednesday because she has donated to Gideon’s U.S. Senate campaign. The other vacant seat on the five-member panel is a position that has been left unfilled by the Maine Legislature, which has been unable to reach agreement on a third-party or unenrolled nominee for 19 months.

The other commissioners, Republicans Richard Nass and William Pattershall, and Democrat William Lee, listened to both Youngbloood and Benjamin Grant, an attorney for Gideon and a former chairman of the Maine Democratic Party, for just over an hour before voting to reject any additional investigation of Gideon. They then voted 3-0 that her PAC had violated the state’s campaign finance law and set the fine.

Youngblood, who filed the complaint, argued that Gideon was in a position of leadership at the Legislature and should be held accountable for the campaign finance violation.

“There needs to be a penalty to demonstrate to other people that these kinds of things, we pay attention to, they are not acceptable, they are against the law and don’t do it,” Youngblood said.

He also noted that he was a leading advocate for Maine’s Clean Elections Law, the state’s publicly funded campaign finance system that allows participating candidates to receive public funds for their campaigns instead of taking private, corporate or PAC donations.

But Grant argued that Gideon had taken all the steps necessary to clear up the record, saying the amount of money in question was “minor in the grand scheme of how much money goes back and forth during an election cycle.”

Campaign finance records show that Gideon used her personal credit card to make donations to PACs working in Maine and to the federal campaign of Emily Cain, an Orono Democrat and former state senator, who was running for Congress at the time. Gideon’s Leadership PAC then reimbursed Gideon for the donations.

The federal donations are the subject of a separate, Federal Elections Commission complaint, also filed by Youngblood, as federal law also prohibits making campaign donations in another person’s name.

It’s unclear when the FEC will act on the complaint. Gideon’s campaign already has acknowledged the violation and paid $3,250 to the U.S. Treasury.

The National Republican Senatorial Committee branded Gideon’s actions an “illegal straw donor scheme” and drove a rolling billboard attacking Gideon through Augusta during the ethics hearing. The NRSC also is running ads on Facebook and Twitter.

Youngblood said he would have brought the complaint even if Gideon was not running for the U.S. Senate. He also said he had no knowledge of the recently launched RNSC campaign against Gideon that was based largely on his complaint.

Asked if he believed what Gideon and her PAC did fit the definition of her being a straw donor, Youngblood said, “No. I don’t think so.”

Grant deferred all comments on the decision to Gideon’s U.S. Senate campaign.

Maeve Coyle, a spokeswoman for Gideon’s campaign, said the commission made the right decision in not launching any additional investigation into Gideon or her PAC.

“Today, the commission continued its tradition of fairness by agreeing not to investigate a complaint that originated from national Republicans and to close this matter,” Coyle said in a prepared statement issued moments after the commission’s vote.