McCAskill appeared on NBC's Meet the Press to address a comment Rove made about how Clinton's concussion and blood clot in 2012 could hurt her in a run for president.
McCaskill says Republicans are speaking out against Clinton because she has, "the strongest resume for president of anyone who has run in a long time"
"I think he's trying to be a part of the conversation. I think we all know what this is. It's a cheap political shot. It's the kind of politics that make people not want to participate and it's too bad," McCaskill said.
Some Republicans say Clinton's record as Secretary of State, on issues such as Benghazi, will hurt her if she decides to run in 2016.
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