House Majority PAC, the biggest-spending Democratic super PAC operating in the House landscape, has upped its final media buys in seven congressional districts, including one where New York City Mayor Michael Bloomberg's new super PAC has gone on the air against the Democratic challenger.

The Democratic PAC added another $100,000 to its TV ad buy in Connecticut's 5th District, an open Democratic-held seat where Bloomberg's Independence USA PAC is set to spend around $575,000 airing ads backing GOP nominee Andrew Roraback. Bloomberg's new group is spending millions over the election's final weeks in support of moderate House candidates from both parties.

House Majority PAC also bought an additional $50,000 in California's 26th District, an open GOP-held seat (upping its total to $490,000); $115,000 in Iowa's 4th District against GOP Rep. Steve King ($285,000 total); $340,000 in the open, Democratic-held Illinois 12th District ($465,000 total); and additional $25,000 investments against GOP Reps. Brian Bilbray (California's 52nd District, $875,000 total), Chip Cravaack (Minnesota's 8th District, $675,000 total), Jim Renacci (Ohio's 16th District, $755,000 total), and Francisco (Quico) Canseco (Texas's 23rd District, $680,000 total).

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