FAIRBANKS — In nearly the same breath Tuesday, Republican U.S. Senate hopeful Dan Sullivan put forward a pledge to fight millions in Outside political spending in Alaska while supporting the Supreme Court case that made that spending possible.

Sullivan held a conference call to propose what he called the “Alaska Agreement” between him and Democratic Sen. Mark Begich that he said he hopes would discourage attack ads funded by wealthy Outside groups.

The plan, modeled after the People’s Pledge of the 2012 Massachusetts senate race, would require both candidates to voluntarily penalize themselves for every ad launched by an Outside group. For every Outside-funded ad, the candidates would donate 50 percent of the cost to charity of their opponent’s choice.

It’s a clever way to circumvent federal election law that bars candidates and political action committees from coordinating their efforts. According to the Washington Post’s reporting on the announcement, groups backed off the Massachusetts race between Democrat Elizabeth Warren and Republican Scott Brown.

“I think one of the reasons that we have confidence in it is because its actually worked before,” Sullivan said during the call. “All it takes for this to work in Alaska is to have Mark Begich’s signature on it.”

But that’s probably not going to happen.

Shortly after the announcement, Begich’s campaign hit Sullivan hard for supporting the Supreme Court decision that has made unlimited spending possible. In the process, Susanne Fleek-Green, campaign manager for Alaskans for Begich, reminded that Sullivan still has a primary to win.

“Sullivan again tried to tell Alaskans one thing, but then quickly revealed the truth today — he supports allowing corporations to engage in unlimited spending in our elections,” she said. “If Dan Sullivan makes it out of his competitive primary, it will be a stark contrast between his put-corporations-first position and Senator Begich’s support for real campaign finance reform including support of a constitutional amendment throwing out Citizens United.”

Sullivan dodged three reporters’ questions on his position on the 2010 Citizens United decision from the Supreme Court that found political contributions from corporations and unions are protected as free speech. The decision has enabled unlimited and anonymous spending pouring in on a big-ticket races, such as an Alaska senate seat held by a Democrat.

Alaska has felt the brunt of this spending and some candidates, including those for governor, have complained that buying media in the lead up to the general election has been expensive and sparse.

Moments after the conference call ended, however, Sullivan took to Twitter to voice his support for the ruling: “I support Cit. United & strong free speech, but that’s not what the AK Agreement is about. In this race, we need to #LetAlaskansDecide.”

For all of Sullivan’s initial dodging on the issue, however, Begich also didn’t definitively say whether or not he will sign Sullivan’s agreement. Instead, Begich pointed to his “Alaska We the People Pledge” that promises to overturn Citizens United. That pledge, unlike Sullivan’s agreement, doesn’t carry any penalties for this election year.

Contact staff writer Matt Buxton at 495-7544. Follow him on Twitter: @FDNMpolitics.