Only two independent candidates appear on the Minnesota November 2010 ballot for State House of Representatives. It is has been discovered that one of them, Al Hein, running in the 31B district, was accidentally put on the ballot even though he did not file any petition. See this story. The 31B district is in southeastern Minnesota. UPDATE: see this story about the problem, published on September 21.
Very few candidates qualify as independent candidates for the Minnesota legislature, because the 500 petition requirement is rather steep. The requirement amounts to approximately 2.5% of the last vote cast, and all signatures must be gathered within two weeks. When Hein came in to file, his county election administrators did not know he needed a petition. Candidates running in party primaries in Minnesota need no petition. So, he was put on the ballot with just a filing fee and a declaration of candidacy, and now the ballots have already been printed.
The 31B district was one of the closest legislative races in Minnesota in 2008. The Republican nominee polled 51.05% and the Democratic-Farmer-Labor nominee polled 48.95%.
Minnesota does not have registration by party. However, Hein was the Democratic-Farmer-Labor Party nominee for that same legislative seat in 2000 and 2002, and he ran in the DFL primary for that same seat, without winning the nomination, in 1998.