Ohio's congressional delegation will remain the same. All 16 incumbents have won re-election in Tuesday's midterm elections. That keeps the delegation at 12 Republicans and four Democrats.
The sweep was expected, with most incumbents holding safe seats after U.S. House districts were redrawn because of population changes in the 2010 U.S. Census.
In partial, unofficial returns, nearly all the incumbents had more than 60 percent of the vote.
U.S. House Speaker John Boehner won election to a 13th term in his western Ohio district, and said he was humbled by his support in the 8th District.
The Republican incumbent easily defeated Miami University professor Tom Poetter.
The Democrat posed little threat in the heavily Republican area that includes the 64-year-old Boehner's home in the northern Cincinnati suburb of West Chester Township. But Boehner's campaign kept up TV and radio ads in the weeks ahead of the election. The campaign also ran TV ads before Boehner's May primary victory over two GOP opponents.