Democratic U.S. Sen. Mark Begich is challenging his Republican opponent, Dan Sullivan, to sign a new pledge that would likely reduce the amount of outside spending in their race by penalizing the candidates if they get support from groups whose donors don't meet certain transparency standards.
Sullivan, however, is unlikely to sign, setting himself up as a potential target for a new batch of negative TV ads.
The pledge -- originally proposed by a California-based super PAC co-founded by a tech entrepreneur, and subsequently endorsed by the Alaska Public Interest Research Group -- is the second one taking on outside money in the Alaska Senate race.
The first, proposed by Sullivan in June, would penalize the candidates for TV or radio ads run by any third-party group, even if its donors were disclosed, by requiring the candidates' campaigns to make a charity contribution equal to half the amount of the third-party spending -- a framework that's been shown to reduce the amount of outside money in campaigns.
Begich, who has had more third-party TV commercials run on his behalf than Sullivan has, refused to sign. He called Sullivan's proposal a campaign ploy, given the Republican opposes permanent legislation to limit spending by outside groups and to require them to disclose their donors.
The new pledge was first floated by a group called CounterPAC, which supports campaign finance reform and has been involved in several other U.S. congressional races.
In a press release, Begich's campaign cited Alaska Public Interest Research Group's endorsement of the pledge.
"Mark Begich agrees with Alaskans that all voters deserve to know where campaign dollars and attack ads are coming from," the release quoted Begich's campaign spokesman, Max Croes, as saying.
In an emailed statement, Sullivan's deputy communications director, Thomas Reiker, responded that the pledge wouldn't work.
"This new proposal would not stop outside ad spending, and we continue waiting for Mark Begich to join Dan in ending all outside spending in Alaska," the statement said.
But Jay Costa, CounterPAC's campaign director, said in a phone interview the pledge "very honestly would keep millions of dollars in untraceable outside money from flooding into this race."
"Dark money" groups who have supported both sides -- such as the Koch brothers-linked Americans for Prosperity, and the liberal-leaning Vote Vets Action Fund -- would likely stop running their ads in the race if they had to provide more information about their donors.
And even super PACs like Put Alaska First, which supports Begich, and American Crossroads, which supports Sullivan, would have to return some of their contributions or pull out of the campaign, Costa said, based on CounterPAC's stringent transparency requirements.
"It's time for both candidates to put political posturing aside and not let small details stand in the way of reaching an agreement that would make this race more accountable to the voters of Alaska," Costa said in a follow-up email. Costa also said in his email: "It's disappointing that Dan Sullivan would so immediately dismiss this opportunity."
Costa's group has already spent more than $100,000 attacking Mike Coffman, an incumbent Republican U.S. House member in Colorado. His opponent agreed to the pledge, but Coffman wouldn't, leading to a TV commercial from CounterPAC posing questions about the donors to the groups supporting him.
"You just don't know who they are. Big tobacco? Russian oil billionaires? Too-big-to-jail Wall Street bankers? The owner of China's largest casino?" a narrator intones in the commercial. "We don't know, and that's just how Mike Coffman wants it."
Costa said his group has been "watching Alaska very closely" and is "prepared to make an even more substantial intervention" in the Senate race, though he declined to say just how much.
Much more outside spending is expected in Alaska during the next few weeks.
The statement from Reiker, the spokesman for Sullivan, said it was "disingenuous" for Begich to agree to a pledge requiring transparency from outside groups solely in the final weeks of the campaign. But Costa pointed to a recent analysis by the Center for Responsive Politics showing more than half the dark-money spending in elections typically comes after Oct. 8.
"There's a real opportunity here to stop the majority of the spending -- at least the untraceable spending," Costa said.