Republicans have a favorable map, but Democratic candidates are on top in several battleground states. It is anyone’s game in the first Fox News Power Rankings for the Senate this cycle.Ticket splitting will make the differenceIf you know one fact about the 1984 presidential election, it’s that Ronald Reagan won in a landslide. With wins in 49 states and a total of 525 electoral college votes, no candidate has ever pulled off a larger victory.You might not remember that in the same election, Republicans lost two Senate seats, leaving them with a total of just 53 in the upper chamber.Outcomes like these used …