The Associated Press (AP) has a story about people migrating internally in the US. It focuses on red Idaho vs. blue Colorado as examples of states attracting people moving in both directions and the longer term results of such moves.
One party controls the entire legislature in all but two states. In 28 states, the party in control has a supermajority in at least one legislative chamber — which means the majority party has so many lawmakers that they can override a governor’s veto. Not that that would be necessary in most cases, as only 10 states have governors of different parties than the one that controls the legislature.
One state - Nebraska - has only one house and therefore cannot have divided control. Divided control is possible in the other 49 states, but existed in only two as this was published some 7 months ago.
There are a handful of battleground states where either party might win depending on how the independents vote. In most states one party dominates the state' politics.
When your home state moves from "battleground" to "dominated" there are two possible outcomes. When it's your party which dominates, you'll tend to be happy with governing policy, and stay.
When it is the other party which dominates, your newly minted political impotence can become a nagging source of low-grade aggravation. If an opportunity to move arises, the aggravation becomes an influence to leave and, while you're at it, to move where the policies are to your liking.
The quoted paragraph suggests a substantial number of such moves have already occurred.
