The question this brings up is: Should you vote in a primary for the candidate who best represents your views but won't win the election, or should you vote for one who is close to your views, but is electable in the general election?
Here in Colorado our Senate Republicain primary was between Pete Coors and Bob Schaffer. Coors won the primary, but Schaffer should have done better in the general election. Coors lost to Ken Salazar(now Sec Int).