It says in the 1982 Almanac of American Politics that Fort Chaffee ("near port Smith") was a major entree point for Cuban refugees. According to the book, the locals were upset over the rumors that all the refugees were criminals and/or homoxexuals (I'm not making this up, I swear), for which Democrats suffered across the board.
This is the only solid item I could find. Other than that, the book says that Carter's loss in Arkansas, coinciding with Bill Clinton's loss in the gubernatorial race, was very unexpected. The Cuban refugee issue must have had more effect across the state than most realized; the economy and Reagan's religious roots probably played a large part as well.