WASHINGTON -- The U.S. Chamber of Commerce stepped up an ad blitz Friday that focuses on House races in solidly Democratic states, betting that control of the chamber rests in places like California, New York and Illinois.

The trade group, which favors Republicans, began airing ads Friday in three Illinois races. That follows its recent investments in eight California contests, six New York races and two more in Illinois. The ads generally attack the Democratic candidate for supporting health care legislation that the chamber and Republicans say hurts job creation. They also say that the health care legislation makes cuts to Medicare, the government's health care program for the elderly and disabled, and increases taxes for the middle class.

Fewer than six weeks before Election Day, Republicans are expected to hold the House majority, but Democrats are still driving to gain the 25 seats they need to take control.

A spokeswoman for the Chamber, Blair Latoff, said the group saw a chance to influence districts where other groups are sitting on the sidelines because there is no competitive presidential or Senate race. She refused to say how much the chamber planned to spend, but Federal Election Commission reports indicate the tab runs into the hundreds of thousands of dollars for each race.

"These orphan districts in places like New York, California and Illinois are critical to maintaining a pro-business majority in the House," Latoff said "We believe our substantial efforts have impacted these races in favor of the candidates who support free enterprise."

Redistricting has played a major role in putting congressional districts in California in play. While outside money isn't pouring into the state for the presidential or Senate races, outside groups are active in about 10 districts. For example, groups have spent nearly $3.3 million in the Modesto-area congressional district, where GOP Rep. Jeff Denham is defending his seat against former astronaut Jose Hernandez, a Democrat. The chamber invested $600,000 in that race last week, but a Democratic group called the House Majority PAC had previously put more than $435,000 into that race. Andy Stone, a spokesman for the PAC, said it was also investing heavily in the three states the chamber is targeting.

"We made significant investments in all those states, in part because we knew that, just like in the last cycle, GOP money would come in at the end," Stone said.

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