WASHINGTON -- A late spending splurge by outside political groups helped Republicans take over the House two years ago. The floodgates are opening again, but this time Democrats say they're better prepared.

The Sunlight Foundation reports that outside groups have spent about $49 million since June 1 trying to help Democratic candidates and about $60 million trying to help GOP candidates.

But some of the Republican support groups are just getting started.

The Chamber of Commerce recently launched a multi-million dollar ad campaign designed to help 20 GOP candidates in California, New York and Illinois.

Deep-pocketed groups led by Karl Rove has ordered millions of dollars of ads for Republican House candidates after previously focusing on the Senate and presidency.

Americans for Tax Reform is also beginning to invest in House races.