Campaign spending on radio and television advertising has crossed the half-billion-dollar mark.
With the $37 million being spent this week on political advertising -- including the campaigns and the Super PACs that support them -- the grand total for this campaign is now more than $512 million, about the amount spent on advertising in the entire 2008 general election, according to an NBC News/Smart Media Group Delta analysis.
Source: NBC News. Read full article. (link)