South Carolina has always been an open primary state. Any registered voter is free to vote in any party’s primary. The Republican Party of Greenville County had filed a federal lawsuit against the open primary back on April 20, 2009, saying it wanted to exclude Democrats from voting in its primary. However, on August 14, 2009, the party voluntarily dismissed the lawsuit.
Ballot Access News
Edited By Richard Winger
The suit was filed by the chairman of the Greenville County Republican Party, and he was ousted in May.
This leaves Idaho Republican Party v. Ysursa, which is in US district court.
I still believe that, when a suit challenging a state-mandated open primary reaches the US Supreme Court, the high court will strike it down.