In Ohio, a presidential battleground state, Democratic Sen. Sherrod Brown is facing a spirited challenge from Republican state treasurer Josh Mandel. In Hawaii, Republicans are hoping former Gov. Linda Lingle can break the Democratic grip on the Senate seat; incumbent Daniel Akaka is retiring.
Earlier this year, the chamber ran ads in eight Senate races — Ohio, Montana, Wisconsin, Virginia, Indiana, Hawaii, Missouri and North Dakota — and 12 House races that hit more than 40 media markets, including the expensive Washington region. Republicans and Democrats estimated the buy at $10 million; the chamber would only say eight figures but did describe the effort as unprecedented in its 100-year history.
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