This fully explains why Alabama has voted for the Republican presidential candidate for every election since 1980, or at the least why they haven't voted for the Democratic candidate.
Straight from the State Constitution
US Law Alabama Law Alabama Constitution
SECTION 182
"Certain persons disqualified from registering and voting. The following persons shall be disqualified both from registering, and from voting, namely:
All idiots and insane persons;..."
Is that really in there ?