Sen. Claire McCaskill (D-Mo.) is asking her supporters to sign a petition in favor of the Violence Against Women Act, days after one of her opponents said she hadn't heard of the bill.

"I know VAWA saved lives and protected children," McCaskill wrote in an email to supporters, referencing her work against domestic violence as a county prosecutor. "It's one thing for Republicans to play political games to try and win elections. But to block this life-saving legislation is going too far. Way too far."

"Any result other than the reauthorization of VAWA is unconscionable. Let's make sure everyone knows it," McCaskill said.

Sarah Steelman, one of the Republicans vying to oppose McCaskill, said last weekend that she was "not sure" what the Violence Against Women Act was in response to a voter's question about it.

"I'm not sure what that is because I'm not serving right now," Steelman said in a video posted online by the Missouri Democratic Party. Her campaign later clarified that she would be open to a Republican version of the bill.

McCaskill didn't mention the comments, but the St. Louis Post-Dispatch speculates that they could become a tough issue for Steelman if she faces McCaskill in the general election.

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