I have far more respect for someone who votes all 3rd party candidates and on the ballot propositions rather than someone that doesn’t vote at all.
You’re right to some degree about high profile races; governor, senator and US representatives are all high power jobs where the candidates have generally been vetted and approved by those in power. However, once you start getting down the ballot for more local offices, there is a lot less scrutiny by both the national and even state party. Basically I wouldn’t rule someone out for commissioner or school board member just because they happen to favor one of the two major political parties; learn about the candidates and their positions, and figure out which one you support more.
