Washington, November 4 (RHC)-- It's Election Day in the United States, where an estimated $4 billion has been spent on the most expensive midterms in U.S. history. Despite the record spending, voter turnout is expected to hit one of its lowest levels in years.

Control of the U.S. Senate has boiled down to about 10 key races, some of which could result in runoffs. Current projections give Republicans about a 70 percent chance of netting the six seats they would need to retake the Senate from Democrats.

Thirty-six U.S. states are choosing governors today and voters across the country are deciding on 147 ballot measures, which include measures to decriminalize marijuana, restrict abortion, raise the minimum wage and require labeling of GMO foods.