As was pointed out by Scott Adams (of Dilbert fame) from a campaigning perspective Trump will damage Ron so badly that even if Ron wins the primary, he will be beaten up so badly he has a poor shot of winning the general election.

The crats don't need a good candidate. They did not have one last time and it did not matter. They will fearmonger the public.

At the same time, they will get every organization and 'charity' to do PSA on voting. Their base may be unenthusiastic, but promised enough free stuff and convinced via media to vote, can still carry the day. 

And that is before any vote tampering. They still have plenty of judges to say we MUST allow ballot harvesting and other practices that make it impossible to stop cheating.