TLDR, but I'd like a citation for those voter fraud investigations. The usual explanation for reduced voter turnout when voter ID laws are applied is the difficulty of obtaining ID (D districts may be further from the relevant offices than R districtsm, and for some reason it costs money and you can't do it by post).

I'm also confused as to what -285% could possibly mean - voters stopped turning out so hard that they ended up voting for the other party twice over?