An independent group supporting President Barack Obama's re-election is preparing a $30 million advertising blitz in six battleground states this fall.

A person familiar with the plans says Priorities USA Action has reserved television ad time in September in Colorado, Iowa, Florida, Ohio and Virginia. Pennsylvania will be added in October.

Priorities USA Action was founded last year by two former Obama White House staffers in response to the proliferation of Republican-leaning independent groups that took place after the Supreme Court eased restrictions on campaign spending.

It has raised just $21 million since its inception. At the same time, the conservative groups American Crossroads and Crossroads GPS have pledged to spend $300 million this year.

News of the ad buy was first reported by The Washington Post.