Just a note of caution....
This is the same game that the democrats played going into 2016. They were sure Trump was the most easily defeated candidate in the crowd, and their crossover support contributed to his early vote totals that help him pull away from the field. Now I don't think Sanders will ever beat Trump, but I also didn't think Trump was going to beat Hillary. So these things don't always work out as planned. It certainly didn't for the democrats in 2016.