The penalty would be limited to $250,000 and once the deal is broken both campaigns would be freed from its restrictions. Rehberg recently called for disclosure of donations to all outside groups, and said that the campaigns were "along for the ride" when it came to big outside spending.
Here's the full letter Tester sent to Rehberg:
I appreciated your comments in the Flathead Beacon last month about third-party expenditures—that you and I are “along for the ride” when it comes to the attack ads neither of us control.
I imagine Montanans are telling you what they’re telling me: these attack ads distract from the issues Montanans truly care about. It’s a shame that third-party organizations are allowed to pollute our records and drag our character through the mud with no transparency and no accountability.
Montanans take great pride in our state’s century-old law banning corporate control over our elections. They passed our law after wealthy corporations literally bought Montana’s elections and power and influence in Washington. You and I should do everything possible to prevent that from happening ever again.
That’s why I’m offering an unprecedented agreement between you and me for this historic election year: Let’s reject and work to keep all third-party radio and TV ads about you and me out of Montana. Let’s reject efforts by outside groups to undermine Montana’s tradition of elections decided by people—not corporations.
I’ve enclosed an agreement that puts some real skin in the game, to give all third-party organizations—those that support you and those that support me—a powerful incentive to keep their advertising away from Montana airwaves. I’ve already signed it, and I look forward to you joining me.
Let’s let only you and me—and our campaigns—do the work of illuminating the issues and the differences that separate us. Such an agreement will give Montanans a clear choice on November 6 without the influence of third-parties willing to secretly spend millions of dollars trying to influence voters.
Given that more than $1 million in attack ads have run against both of us, I believe this agreement is fair, and I’m not looking to start a series of counter-proposals designed only to make headlines. I’m interested in a real, good-faith commitment for both of us to campaign on our records, without the influence of third-party organizations.
Rather than just go “along for the ride,” let’s do our part to steer this campaign toward Montana’s values of honesty, accountability and transparency in elections. The people we serve deserve no less.
If you don’t agree to this agreement by Friday at 5:00 p.m. MST, I will assume you are not willing to participate. I look forward to hearing from you soon.