I would disagree with you to an extent.
It does appear that Donald Trump is the only one on our side with a solid chance of winning the Republican Primary. But any Republican in the race would have a chance to beat Hillary or Bernie, if they were able to win the Republican nomination in a fair and open process.
But if my Grandmother had wheels, she would be a bicycle.
Barring some massive upset, Donald Trump is going to win the Republican nomination. I am not saying we have to get behind the frontrunner, or anything stupid like that. People should vote for whomever they want. But at the end of the day, we all have to be singing from the same hymnal.
The only way we can screw this up is by defeating the primary process and pissing off a large portion of our electorate. We cannot let that happen.
Apparently, you can't stop it.
At any rate, I'll vote for whoever our last man standing happens to be and I believe that it will be Trump, but would be perfectly happy with Cruz and be praying my butt off that he attains the WH.