Rep. Thomas Reynolds, a once-powerful lawmaker who saw his fortunes fall with that of the House Republicans, will announce Thursday he is retiring from Congress, The Associated Press has learned.

The 57-year-old lawmaker from Amherst, N.Y. will announce he will not seek another term at a news conference scheduled for noon Thursday in his western New York district, according to a person familiar with Reynolds' decision. The person spoke on condition of anonymity because the announcement hadn't yet been made.

Before Thursday, 28 House Republican incumbents had indicated they would not run again, giving Democrats an opportunity to expand their majority this fall.

Reynolds was once considered a potential speaker of the House. He chaired the National Republican Congressional Committee for two elections, guiding his party to strong wins in 2004 but in 2006, it lost control of the House that the GOP had held for a dozen years.

He raised hundreds of millions of dollars for his party, but the committee has come under intense scrutiny in recent weeks after revelations that hundreds of thousands of dollars are missing. The missing money has prompted an ongoing investigation into a former treasurer for the group.

On the House floor or in his GOP offices, the barrel-chested congressman would often hammer at Democrats in the regional accent often called "Buffalo English," using the smashmouth terminology of football to describe political contests.

As his party faced stronger challenges from Democrats, so did Reynolds.

To win his current term, he defeated Democrat Jack Davis in a contest that cost both sides millions of dollars. That race was dominated by debate over Reynolds' role in the Mark Foley congressional page scandal, with Reynolds saying he did everything in his power to force Foley out of Congress after he learned of inappropriate communications with young pages. Then, just weeks before Election Day a powerful snowstorm crippled much of Reynolds' district, shifting the public's attention to the emergency response.

For five terms, Reynolds has represented represents the 26th Congressional District, a seven-county region that stretches from the Rochester area to the Buffalo suburbs.

A former state legislator, Reynolds spent much of his time in Congress advocating for lower taxes. He may be remembered best in his district for the winning effort in 2005 to save the Niagara Falls Air Reserve Station, which had been slated for closure in an intense round of military cost-cutting.

Reynolds is the second New York Republican in the House this year to decide not to seek re-election. Syracuse lawmaker James Walsh made the same decision in January. Currently, there are six New York Republicans in Congress, half the number at the start of the decade, and the decisions by Walsh and Reynolds suggest the party may face more election losses this year.