Republican Eric Brakey, independent Sen. Angus King and Democrat Zak Ringelstein at Maine Public's Senate Debate on Oct. 30, 2018. Credit: Rebecca Conley | Maine Public

Independent U.S. Sen. Angus King is sending a check for $5,000 back to Exxon Mobil.

The check reflects a donation by the Texas-based oil and gas corporation to King’s campaign this election season. King is returning the money after being challenged to do so by his Democratic rival in the race.

It happened about 10 minutes into Maine Public’s Senate debate Tuesday afternoon. Democrat Zak Ringelstein was discussing his support for a green “New Deal” to convert to 100 percent renewable energy by 2035 as a way to address climate change. And then Ringelstein, who has been critical of King and other candidates who take money from political action committees, lobbyists and the fossil fuel industry, turned to King and issued a challenge.

“Meanwhile, Angus King is taking money from Exxon Mobil. And I’d like to ask him: Angus, will you stop taking money from Exxon Mobil and fossil fuel industries … Will you give the money back?” Ringelstein asked.

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When King said yes to both questions, Ringelstein said, “Phenomenal. Thank you. Can we do a press conference tomorrow?”

The unusual concession ended with a handshake between the two candidates. And while there was no press conference the following day, King agreed to discuss it between campaign stops in Westbrook.

“I think the check has been cut, and nobody buys my vote, but Zak was just hitting me over the head with it, and I think it was a red herring and the easiest way to take care of it would be to say, ‘OK, we’re gonna not do this,’” King said.

It’s a red herring, King said, because he discloses all his contributions and wasn’t aware that Exxon Mobil had made a $5,000 donation. It’s small enough that it doesn’t crack the top 100 of the groups or individuals that have given to him. In fact, the League of Conservation Voters, which supports candidates who support sound environmental policies, donated far more. It gave King’s campaign $30,000, which comes in at No. 5 for King’s largest donations.

King’s two opponents are skeptical that Exxon Mobil is the only fossil fuel company to have ever supported King’s two races for federal office. Ringelstein said the check to Exxon Mobil shouldn’t close the deal that King agreed to with a handshake.

“He agreed to the entirety of the fossil fuel industry, if you look back at the clip, so we want to make sure that Angus is living up to what he said,” Ringelstein said.

According to the Center for Responsive Politics, a nonpartisan research group that tracks money and lobbying around the country, King has received more than $124,000 from energy and natural resource groups. That includes wind, solar and fossil fuel companies. But King’s biggest donors in this group are from renewable energy companies, such as the American Wind Energy Association, which gave him $9,000.

“At the end of the day that’s just a small portion of the donations he’s received from the energy industry,” Republican Eric Brakey said.

Brakey is critical of King for taking money not only from Exxon Mobil and the fossil fuel industry, but from renewable energy companies as well. But Brakey’s own campaign has been the beneficiary of an independent, out-of-state PAC that has spent more than $1 million on ads critical of King and financed primarily by a Texas billionaire. That’s the real problem of campaign finance, King said.

“To put it in context, I’ve had 22,000 donations, about two-thirds of which are from Maine and over 80 percent are under $100,” King said.

King also said he’s never taken a vote where he’s thought about a contribution, and he maintains that he is one of the least favorite senators of the fossil fuel industry.

This article appears through a media partnership with Maine Public.