Yes, Cornyn needs to go.
With multiple candidates the winner must received more than 50% of the primary vote.
That means if Cornyn does not receive more than 50% a run-off is required. . .and that is where Cornyn will loose as the run-off election will be stacked against him because Cornyn will be facing the fact that over 50% of primary voters did not vote for him the first time around. Basically, Cornyn would be facing a primary electorate that already voted against him. (Cruz won the primary this way.)
If a run-off comes then the other candidates MUST throw their support behind whoever ranks highest (other than Cornyn).
If it comes to a run-off, Cornyn will reveal his true RINO/RAT heart and attack and attack personally Stockman.
I think Stockman has the best chance in a run off. . .but that’s just me.
Cornyn will end up in a run off because he is the incumbent. Don’t know enough about the others, but a change is long overdue.