Fascinating story.
Reading this article and the Wikipedia bio on Don Seigelman, he was a somewhat controversial political character. As a politician needing campaign funds and support from certain "bases", he had to make compromises to win elections.
Let's add in the razor thin margins common in most American elections. All sorts of things can happen to flip the final result one way or another.
Which leads to my next point. A shift of 6,000 votes is really only 0.5% of the total votes of that Alabama election. Let's acknowledge that there was no widespread cheating in this election. The little bit of cheating probably did change the result, but to suggest the election vaulted an unpopular Republican candidate over a popular Democrat is rather judicious.
The razor-thin margins are a recipe for encouraging a little bit of cheating. If USA really doesn't want these controversies, it should look at alternative systems of democratic governance.
But I think the USA likes this kind of drama.