Democrats are comparing Indiana Republican Senate candidate Richard Mourdock to a schoolyard bully in a new radio ad coming out this week.

Mourdock, the state treasurer, toppled Sen. Dick Lugar earlier this month in the GOP primary in part on a platform that includes a promise to oppose bipartisan compromise. He's also compared the current climate to the era just before the Civil War.

Democrats don't think that will play well with Indiana voters outside the Tea Party faithful who nominated Mourdock, and the ad accuses him of a "my way or the highway" atitude.

"We all know 'my way or the highway' is the way certain folks work," the ad says. "Like schoolyard bullies, for instance."

The spot segues to an example of a mean-sounding schoolyard tough saying: "Hey, kid ... gimme your lunch. Or else."

"But for politicians? From Indiana?" the ad continues, before bringing up Mourdock.

"Mourdock's even said, quote, 'The highlight of politics, frankly, is to inflict my opinion on someone else,'" the ad runs.

A source that tracks ad buys told The Huffington Post the buy is $21,000 for statewide play starting Sunday.

Listen to the ad here.

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