As the 2016 election dramatically revealed, the United States has split into two political nations. In each of those distinct coalitions, the majority Republican or Democratic Party separately controls at least two-thirds of the presidential Electoral Votes, the seats in Congress, and the governorships. That leaves the balance of power with roughly 20 percent of the states and voters—from Ohio to Wisconsin, and Colorado to Arizona—where partisan control is up for grabs and the nation’s political control is determined. For the foreseeable future, significant shifts in the overwhelming numbers on each side seem unlikely. CONT.
Richard E. Cohen, Cook Political Report