President Barack Obama has been dealt a double setback after Republican wins in two seats, including one billed as a referendum on his economic policies.
In New York, Republican Bob Turner won a key election to succeed Democratic Congressman Anthony Weiner, who quit in June over a sex texting scandal.
The retired media executive is the first Republican to take office in New York's ninth district since the 1920s.
Meanwhile, Mark Amodei defeated Democrat Kate Marshall in Nevada.
Addressing jubilant supporters after his win, Mr Turner said people had voted against the president's "irresponsible" fiscal
policy.
A name like Weiner and he's flashing his wanger on the net?
“If you trust in yourself, and believe in your dreams, and follow your star. . . you'll still get beaten by people who spent their time working hard and learning things and weren't so lazy.”
The funny thing about the New York seat is that the Democrats in Congress supported Weiner until they concluded that the seat was in a solid Democrat district, and they would certainly retain it in a special election. Then they told him to resign.
That particular race, however, was more influenced by an attempt to chastize Barry about his sometimes-ambiguous support of Israel. The guy who won is in his 70's.