If Sen. Mary Landrieu (D-La.) loses Saturday's run-off election -- as she is very likely to do -- the Deep South will not have a single governor, senator  or state legislature that is in Democratic hands.

That's not necessarily permanent, of course, but it at least marks the end result of a long-term trend in the region toward Republicans. It's been stop-and-start; once a Senate seat or governorship has gone from blue to red over the past 30 years, it has occasionally flipped back the other way. And, particularly as demographics in the South shift, Georgia might start shifting back in the other direction. This is likely a nadir for Democrats, not a final resting place.

Using data from the National Conference of State Legislatures, we created this animation to illustrate how control of the state house, governorships and seats in the U.S. Senate has evolved in the states of the Deep South since 1978. (The number of seats in the House of Representatives has similarly become more red, of course.)

If Landrieu manages to win the run-off, Louisiana will remain yellow, as it is currently, with a senator from each party. That will likely hold until at least 2020.