Earlier today a saw a news article criticizing the tea party movement for replacing more likely winners in the republican primary with candidates of our own choosing. The part they seem to miss is that a Republican victory is not necessarily a victory for core American values.
The important question is this: Just how much importance should we place on likelihood of winning? I think we should certainly give some value to the traction a candidate has, but CERTAINLY it shouldn't take such priority that we use our precious vote to support and vindicate republicans that well help worsen the situation by being soft on important issues.
There should certainly be some threshold of compromise with the left at which we say "That's too much for me." and put our vote to a more ideal dark horse candidate. As bad as Obama is, I tend to think McCain winning the last presidential race may have held off the flurry of aggressive left policies, but would have weakened the conservative element of the republican party even further. All of the reaching across the aisle and compromise would be vindicated, and we'd likely hear more along the lines of "Hold your nose and vote republican" this election.
Ultimately, your vote is your voice, and with it you can only say "I want that." If we tell them we want candidates that are soft on conservatism, will they not give them to us? Next election let's have even MORE Republicans bemoaning our takeover of their party. And more importantly, a greater portion of the American people who will support the more conservative representatives we choose over the republican party's career politicians.