I just found this, regarding cross over voting in run offs, from Pearl Cty MS...
PRIMARY ELECTIONS
Party candidates are nominated through primary elections. A voter may vote in either partys primary, and cast a ballot for that partys nominees to the general election. If no candidate receives a majority of the votes in a primary, a run-off is held between the top two vote-getters.
A voter who votes in the primary of one party may not “crossover” to vote in the run-off of another party.
Not that it really answers the question ;-/
>”A voter who votes in the primary of one party may not crossover to vote in the run-off of another party”<
That being the case, Thad won’t have a chance in a Runoff.
Thanks Jane Long!