Louisiana voted 52% for Bill Clinton in 1996. Think about that for a minute.
This happened because, at that time, Cajun Catholics voted with black Democrats, leaving White Protestants in Northern Louisiana in the minority. This was the Edwin Edwards coalition, but it also elected John Breaux, Gillis Long, Chris John, Kathleen Blanco, and Mary Landrieu to office.
The national Democratic Party made some major mistakes. One was allowing Democrat Buddy Roemer to switch parties, leading to the tainted Edwin Edwards (D) having to be endorsed by Republicans against the Klansman David Duke (R) in a Governor's race. Roemer was a whiny blowhard in his way, but he would have been on board for the national ticket in 1992 if he could have been persuaded to stay. The other was in allowing Murphy (Mike) Foster to switch to the GOP to run for Governor. Foster could have won as a Democrat, but Democrats got behind the ill-fated Cleo Fields challenge; this was the first step in undoing the black-Cajun coalition that could have made Louisiana as Democratic as Virginia is now.
The running-off of MODERATE Southern Democrats who were loyal to the National Democratic Party was the biggest strategic mistake of their lifetimes. This made the exodus of blacks during Katrina and the trends toward the GOP during the Obama years to be impossible for the Louisiana GOP to withstand. It made Mary Landrieu unelectable. Cajun Catholics' loyalty to the Democratic Party has been weakened by the National Democratic Party's intransigence on social issues. Democrats have opted for uniformity on abortion and SSM at the expense of electing pro-life Democrats from places like Cajun country that would be supportive of most of the Democratic agenda.
--Bubba did swell in North LA in 1996. Won it. In fact, the great mystery to me is why did he do so well there, but not win Mississippi because in my personal experience, they seem like the same kind of people to me.
--Buddy Roemer is an idiot and will always do what he wants
--Mike "Murphy" Foster could not have won the primary as a D, there were no political bosses to make that happen. The Democratic field had, besides Cleo Fields, Mary Landrieu, Lt Governor Malinda Schwegmann, and wealthy self-financed Baton Rouge businessman Phil Preiss. The only Republican was flaky dumbass Buddy Roemer making his "comeback". He chose the correct path to be governor. He's a lousy person from a historically horrible family, so there really was no reason to try to kiss his butt anyway.
--Blanco got elected with the coalition you speak of after the "mistakes" you speak of, and it could happen again with the right candidate. Just as John Bel got elected with a variation of that coalition (though his map follows more of a national Democrat trend).
--If you think Louisiana could be comparable to Virginia in any parallel universe you can create, you need to put the crack pipe down.
--Post-Katrina moved the population around, but the demographics of the state have stayed the same, with a small steady rise in the % of African-American voters. I guess maybe it sparked a modest increase in Hispanics as there was an influx of mobile labor after the storm and Hispanics are the most mobile of labor. They still remain least likely to register and vote.
One other interesting thing about 1996 was when Mary Landrieu first got elected, it was by the skin of her teeth as she barely beat known fundie grifter Woody Jenkins, and actually ran behind Bubba. There was crossover voting all over the place in that elections. In rural areas there were plenty of Bubba-Jenkins voters and in the metro areas there were Dole-Landrieu voters. There was definitely a trend based on educational attainment that in many ways presages the current era.