President Barack Obama-supporting super PAC Priorities USA came out with a new television ad on Monday that goes after GOP frontrunner Mitt Romney for his "world view," based on his wealth and economic platform.

"He made millions off companies that went bankrupt while workers lost promised health and retirement benefits," a voice-over says in the video. "His own tax return from last year reveals he made $21 million, yet paid a lower tax rate than many middle class families."

The ad will air in four swing states -- Florida, Iowa, Virginia and Ohio -- starting on Monday. It features a single photo for the entire 30 seconds: Romney with his then-colleagues at Bain Capital holding money.

The ad is part of a wider effort to paint Romney as being out of touch with average Americans based on his wealth -- the candidate has said he is worth between $150 million and $200 million -- and his policies on taxes and welfare.

"Romney's proposing a huge new $150,000 tax ­cut for the wealthiest one percent while cutting Medicare and education for us," the ad says. "Mitt Romney: If he wins, we lose."