Your theory requires that of the 1,318,255 Alabamians that voted for Trump in 2016, many will cross over and vote for Doug Jones.
Doug Jones got 673,896 votes in 2017. That's a difference of 644,349 votes, and you are going to tell me that 644,349 people who voted for Trump are going to then vote for Democrat Doug Jones?
I don't think so.
They don’t have to vote for Jones... they just have to NOT vote for Moore... and that is certainly possible. Don’t tell me that people skip races on the ballot if they don’t like their party’s candidate.
Moore took a race that he should have won by at least 10 and lost... no reason to trust anything with him on the ballot....