Republican Rep. John Boozman soundly defeated incumbent Democratic Sen. Blanche Lincoln, with 391,177 votes to Lincoln's 262,927, CBS News said.
Analysts said Lincoln was paying the price for her votes on the federal healthcare overhaul and the economic stimulus package.
The Democratic incumbents in the state's 1st and 2nd Districts, Marion Berry and Vic Snyder, chose to retire rather than face tough campaigns, with Republican Tim Griffin declared the winner in the 2nd over Democrat Joyce Elliott and GOP candidate Rick Crawford defeating Democrat Chad Causey in the 1st District.
Republicans took three of the four House races, with a single Democrat, incumbent Mike Ross, winning a seat.
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