Today, the same geographical split exists. But it exists inside the Republican Party.
Last week, the House of Representatives passed the American Taxpayer Relief Act -- a tax cut of more than $3 trillion over the next 10 years. The bill passed by a vote of 257-167.
In order to prevent the "fiscal cliff", this bill required some degree of bipartisan support. And John Boehner (R-OH) managed to convince 36% of his caucus to vote for the bill.
However, the vote breakdown shows a huge geographical split inside the Republican Party:
|Original Slave States (1776)||1||29||3.3%|
Here is a map showing the breakdown by state. Orange shows where a majority of the Republican Representatives voted for the bill. Red shows where they carried the state by 3 or more votes.
This shows a split in the House that isn't between Republicans and Democrats. It's between Northern Republicans and Southern Republicans.