The DISCLOSE Act is legislation co-sponsored by U.S. Sen. Patty Murray that would force corporate and union funders out of the shadows by making them issue disclaimers at the end of political ads just like politicians do, e.g. "I'm Patty Murray and I approved this message."
Murray co-sponsored and voted twice for the DISCLOSE Act, a bill that would require corporate and union-backed groups to disclose their donors, but the legislation fell short of the 60 votes needed to overcome a Republican filibuster last summer.
Rossi spokeswoman Jennifer Morris said in an email that he would not have supported DISCLOSE if he were in the Senate, citing "special interest loopholes" and "incumbency protection" built into the legislation.
Morris told me the same thing right before a Republican filibuster killed the bill in late September.
"It’s the same bill they considered earlier this year," she said when I asked her how Rossi would vote a day before the GOP filibuster. "The same problems exist with the bill currently under consideration which existed previously, including the loopholes for unions."
The loopholes she's talking about are arcane (here's an explanation) and are not related to full disclosure on TV ads; they shield small donors, like union members who pay dues of around $400, from having to disclose their contributions on campaign finance reports.
However, if a union is the top contributor to an attack ad—even if the union is relying on tons of small union donations to pay for it (the GOP's red flag with the bill)—the big union that cut the check to pay for the TV ad would have to stand by the ad publicly on TV just like a corporation.