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Republican Tom Cotton turned a once-close contest into a cakewalk, thumping incumbent Sen. Mark Pryor (D) in Arkansas' important Senate race. CNN and NBC called the race for Cotton as soon as polls closed.

The race was one of the most hard-fought contests in the country, and in the early going it seemed like either candidate had a decent chance to win. Yet in March, Pryor's critics piled on him for saying Cotton, a military veteran, felt a "sense of entitlement" because of his service. Pryor never recovered, and polls in the closing weeks of the campaign showed him trailing by considerable margins.

President Obama's horrific sub-30 approval rating in the state certainly didn't help Pryor either.

In picking off Pryor, Cotton pushed the GOP closer to its first Senate majority since 2006. Republicans now need a net gain of only four more seats to flip the upper chamber.