Could libertarians and other fringe candidates decide who controls the Senate next year? With Republicans and Democrats locked in a number of tight races, it’s possible that marginal candidates in states like Arkansas, Alaska and *North Carolina — all places crucial to GOP hopes to win Senate control — could play a small but decisive role.

In Arkansas in 2008, Democratic Sen. Mark Pryor‘s re-election was such a sure bet that no Republican even bothered to challenge him. Pryor’s only real competition was a Green Party candidate who got 20 percent of the vote. Now, Pryor is locked in a toss-up race with Republican Rep. Tom Cotton, and there are two fringe-party candidates who could affect the outcome.