Cross-posted from the Wonk Room.

Sen. Claire McCaskill (D-Mo.), after a recent vote to protect coal polluters at the expense of children’s health, is now attacking the League of Women Voters. The 91-year-old good-government organization is running television spots that hold McCaskill and Sen. Scott Brown (R-Mass.) accountable for voting to block enforcement of Clean Air Act rules that limit greenhouse pollution, threatening the hundreds of thousands of children with asthma in their states. Watch the McCaskill ad:

Brown attacked the League of Women Voters for partisan “demagoguery.” Now McCaskill is also on the attack, accusing the league of being “bad guys,” a “tacky” front group “hiding donors behind the cloak of their good name”:

McCaskill also took aim at the League of Women Voters, who she said is “fronting for somebody who ran the ad. … At a minimum, I think the League of Women Voters should not hide behind Citizens United and should be transparent about who’s paying for the ad,” McCaskill said. “I think that’s really tacky for an organization who’s prided itself on transparency and good government, for them to become part of the bad guys who are hiding donors behind the cloak of their good name.”

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“These are our ads,” League of Women Voters President Elisabeth MacNamara told Politico. “This is about the issue of public health and the public knows who is speaking. We’ve stood behind and fought for the Clean Air Act for 40 years. At issue is Sen. McCaskill’s vote, which has endangered the public health.”

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