University of California Political Science Professor Louis Desipio says the Senate race between Democrats and Republicans is “within the margin of error”. “The Democrats are pretty confident about being able to change the majority in the House of Representatives and probably have a 15- or 20-seat majority,” Mr Desipio told News24. “The real question is about the Senate. The Republicans currently have a three-seat advantage; they’re certain to lose one of those. “All of the other races are within the margin of error.”