The purpose of having elections is for individuals to specify who they want to win a given race, not who they think will win.
Voting for a candidate you think will win does absolutely no good. Nor does it make sense. (If you’ve a desire to do that, there is something called a Poll that you should look into.) It also gives an incorrect view of how much support a candidate/party really has. So don’t follow the herd. Use the voice you’ve been given to chose the best person for the job.
In Reality
No election is so dire that you shouldn’t vote with your heart (Heart? Did I just say that?). The country won’t fall apart in 4 or 8 years. It’ll just get mildly flubbed. So don’t get caught on an emotional wave. Keep your head and be rational yet realistic.