SIOUX FALLS, S.D. (AP) — A Libertarian candidate who some say was a big factor in a 2002 U.S. Senate race in South Dakota could be a factor again next year.

The Argus Leader newspaper says Kurt Evans will seek the Senate seat held by Democrat Tim Johnson, who isn't seeking re-election after three terms.

Northern State University political science professor Ken Blanchard says Libertarian candidates typically take votes away from Republican candidates. Some people think that's what happened in 2002, when Republican John Thune lost to Johnson by just 524 votes — with Evans getting more than 3,000 votes.

Four candidates are seeking the GOP endorsement to run for Johnson's seat this time around. There's only one Democratic candidate so far.

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