Americans for Prosperity's Missouri branch is spending another $2.1 million on ads against Sen. Claire McCaskill.
The television and digital ad campaign announced Wednesday by the Koch-backed group criticizes the Democratic incumbent for her support of former President Barack Obama's health care law.
McCaskill is running for a third term in November in a state President Donald Trump won by 19 percentage points. She's up against Republican Attorney General Josh Hawley.
McCaskill spokesman Eric Mee in a statement said the ad is misleading. He said McCaskill is the only candidate in the race working to protect Missourians' health care.
Americans for Prosperity also on Wednesday announced an $820,000 ad campaign against Democratic Wisconsin Sen. Tammy Baldwin and a $2 million ad buy against Democratic Senate candidate Phil Bredesen in Tennessee.
