One other bright spot for Pennsylvania Democrats was the victory of Representative Tim Holden over his Republican colleague, Representative George W. Gekas.
In a primary faceoff between two veteran Democratic incumbents, voters in Ohio delivered a victory to Representative Marcy Kaptur, a progressive from Toledo, over Representative Dennis J. Kucinich, leaving him without a seat in Congress for the first time in 16 years.
Mr. Cao, a freshman Republican from New Orleans and a Vietnamese-American representing a predominantly black district, was elected last year in an upset victory over Representative William J. Jefferson, a Democrat who was under indictment at the time and has since been convicted of federal corruption charges.
"This is a victory," said Representative Lincoln Diaz-Balart, a Florida Republican who fought for the restrictions.
Senator Arlen Specter, the four-term Republican from Pennsylvania, won a narrow 16,000-vote primary victory over Representative Patrick J. Toomey.
"This is a huge victory," said Representative Jos?. Serrano, Democrat of New York, who has fought for years to close the plant, which is in his district.
"I just want to declare victory," said Representative Tom DeLay of Texas, who was re-elected by his party as House majority whip.
In the northwestern corner of the state, the Democratic Congressional candidate, Kathy Dahlkemper, scored an upset victory over Representative Phil English, a seven-term Republican.
COLUMBIA, S.C. — Ed Rollins, the veteran campaign operative who helped engineer an Iowa straw poll victory for Representative Michele Bachmann this summer, has stepped down from day-to-day operations of her presidential campaign, a spokeswoman for Mrs. Bachmann said Monday night.
In his election night victory speech, Representative John A. Boehner of Ohio, the presumed new House speaker, vowed "to take a new approach that hasn't been tried before in Washington by either party".
