What's Wrong with a Protest Vote?

James Dobson, who is this year supporting Donald Trump, voted for Howard Phillips instead of the GOP nominee Bob Dole in 1996. This year various Christian leaders want all Christians to fall in line behind Donald Trump. Janet Porter is the latest far right crusader who exhorts Christians to vote for Trump.
Theology professor Wayne Grudem told us voting for Trump is a moral choice. In 1998, Grudem raised a standard for elective office that he has now repudiated. This year Dobson isn’t protesting but it was okay in 1996.
Why isn’t it an acceptable choice for evangelicals to protest vote in 2016?
Of course, it is acceptable, even honorable to vote one’s conscience. Between now and election day, Christians will be pressured to fall in line with the GOP. We should vote our convictions. My conviction is not to vote for someone who is unfit. In my mind, that conviction eliminates Donald Trump and Hillary Clinton. Oddly enough, I am on the same team as Glenn Beck in this matter. I wonder if he minds having a “liberal bastard” on his team.
I am still exploring options but have no plans to vote for either of two majors.
In my mind, the two party system hasn’t served the people well. I think it is time to invest in alternative parties and even if I vote GOP in the future, I will not discourage anyone from expressing their freedom of conscience in a third party way.