The S.C. chapter of the American Civil Liberties Union is challenging a state law that won't let a candidate run independently (or with another party) for an elected office if he loses a party's primary nomination for that office. This all came up over the recent Eugene Platt controversy on James Island.

From the ACLU:

In the first case of its kind, the American Civil Liberties Union filed a lawsuit in federal court (on August 7) challenging the South Carolina election rules that prevent a candidate seeking the nomination of more than one political party from appearing on the general election ballot if that candidate wins one party's nomination but loses another's. South Carolina is one of only four states that permits fusion voting, which allows multiple political parties to nominate the same candidate, but also has a so-called "sore loser" statute disqualifying candidates who have been selected by one party but rejected by another. The ACLU brought this legal challenge on behalf of the state Green Party, a disqualified candidate for the state House of Representatives and a South Carolina voter.

...

In its brief, the ACLU charges that South Carolina's election scheme imposes an unjustified burden on the First Amendment's free association rights of Platt and voters who are supporting him as well as the Green Party's right to select its preferred candidate. The ACLU is also seeking an injunction requiring the state to place Platt's name on the ballot for the general election in November.

The lawsuit was filed in U.S. District Court in Columbia. You can see the various court filings for yourself, and The Post and Courier also has a story on the issue, with a few more quotes and details:

Chris Whitmire, public information officer for the State Election Commission, said he could not comment as of late Thursday afternoon because the commission had not seen a copy of the lawsuit. He cited a state statute as the basis for the commission's rejection issued in late June.