At Roll Call, Stuart Rothenberg writes:
There probably isn’t a better demonstration of the nation’s partisan political polarization than the makeup of the Senate. Only 17 states have split delegations, while 33 states have either two Republicans or two Democrats (or two senators who caucus with the same party, in the case of independents).
Compare those numbers to the Senate makeup three decades ago, and the change is clear. After the 1982 elections, 24 states had split delegations, while 26 had two members of the same party.
Some of the changes show how state (and national) politics have evolved.
Thirty years ago, Kentucky had two Democratic senators, Walter Huddleston and Wendell Ford. But in 1984, Ronald Reagan carried the state by almost 20 points, running so strongly that he helped drag in an obscure GOP Senate nominee. That upset winner, Mitch McConnell, narrowly defeated Huddleston to begin the state’s transformation into a Republican stronghold in federal races.
...
After the 1982 elections, most Southern Senate seats were split between the parties. The exceptions were Arkansas and Louisiana, with two Democrats each, and North Carolina and Virginia, with two Republicans each.
Now, the only Southern states with split Senate delegations are Arkansas, Louisiana and North Carolina. Each of those states has a Democratic senator up for re-election, and in the current partisan environment, that’s an obvious problem for those incumbent
