I'm not sure how 48% of voters voting for n number of different 3rd party candidates shows that 3rd party candidates are a viable option. That's kind of what we have now. Two main party candidates getting enough voter share to win the election, followed by a lot of 3rd party candidates getting an insignificant number of votes.
Maybe voting for 3rd party candidates will encourage main party candidates to adopt watered down versions of the 3rd party platforms in an attempt to lure their voters. They probably couldn't adopt their full platforms because it would alienate other voters that don't share the 3rd parties extreme views.