Cochran's campaign staff has doubled since June 3rd.
McDaniel, in terms of percentages and turnout, probably "maxed-out" on June 3rd. Cochran still has room to grow among moderates, old people and Democrats.
Can they vote in the run-off if they didn't vote in the first round?
Yes.
Mississippi voter registration is non-partisan. There is no such thing as a "registered" Republican or Democrat in Mississippi. As long as they did not vote in the June 3rd Democratic primary they can vote in the runoff.
All of the polls out there, including the Chism poll, only polled people who had voted in the June 3rd GOP primary. This may prove to be problematic, as a major component of Senator Cochran's campaign is to court voters who did not participate on June 3rd.
