The Post looks at who’s spending what this election cycle.

More than 20 major political advocacy groups plan to spend well over $400 million on campaign contributions, issue-based advertising and other election-related efforts this year, according to an informal canvas of many of Washington’s largest and most influential organizations. When added together with spending by candidates and parties, political expenditures in the 2010 cycle already have topped $2 billion, according to a running tally by the nonpartisan Center for Responsive Politics.