(CNN) – With 33 seats contested in the U.S. Senate, millions were spent as the GOP sought to re-take the chamber.
Republicans had the advantage of having to protect only 10 seats while Democrats had to defend 23, many in narrowly divided swing states. In addition, several veteran Democratic incumbents, mostly moderates, announced they would retire, making it potentially even easier for Republicans to win those seats.
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But as the clock ticked down to Election Day, and as certain Republican nominees faced negative headlines in key races, political observers noted it might be an uphill battle for the GOP in the final stretch of the election.
Check back here for CNN's projections of some of the most closely-watched Senate races this cycle.
– CNN's Ted Barrett and Dan Merica contributed to this report.