The Republicans in Democrat Primaries will probably go far toward choosing the nominee even though their votes in the election itself will have no impact as their states will vote for the Democrat. Those Republicans have much more in common with the Bushes and McCain et al than with those unwashed southern types and many of them would, as with the DNC, prefer to lose the election to winning with a conservative.
In 2008, Hillary actually edged out Obama in primary votes. Democrats recognized that too much of Hillary’s strength came from republican states and adjusted accordingly. Republicans should be so smart.