I agree with JimB on most of his previous post.
I will add that GaryD made a good point, based on his cited article by the historian: The use of state admission after the Civil War that added states that are now essentially Republican.
I think the article said that post-Civil War that the Republican Party started to ally with Big Business.
It is also true that the Electoral College was established BEFORE the very formation of the Republican Party. Also note that the Electoral College has evolved from its inception. And there was debate by those writing and discussing the US Constitution about the merits of the EC.
As JimB said, perhaps the Republicans post-Civil War "played the game better" to help the party then and today.
