Maryland Delegate Richard Weldon, who represents western Maryland, was re-elected in November 2006 as a Republican. However, in September 2008, he changed his registration to “independent.” He is the first Maryland legislator to be anything other than a Republican or a Democrat since 1934. Here is the article about Weldon on Wikipedia. Unfortunately, it doesn’t say why he switched to being an independent.
All Maryland legislator have 4 year terms and all are elected in midterm years. Weldon says he won’t run for re-election in 2010.