(CNN) For the second time this month, Republican President Donald Trump failed to carry a Republican gubernatorial candidate across the finish line in a deep-red state. Last time, Kentucky was the stage. This time it was Louisiana.

Make no mistake: Louisiana is a deeply red state. Trump won it by 20 points in 2016 . Currently, the President's approval rating percentage in the state is in the 50s. His last minute visit to Louisiana last week wasn't enough just as it wasn't enough in Kentucky on the eve of that election.

Like with Kentucky -- and indicative of the Trump era generally speaking -- the election returns showed Republicans had key abatements of support in urban and suburban areas.

Edwards emerged with 90% of the vote in urban Orleans Parish and 66% of the vote in partially urban and partially suburban East Baton Rouge Parish. They are home to the two most populous cities (New Orleans and Baton Rouge) in the state. Trump did lose both of those in 2016. Yet Democrat Hillary Clinton only won Orleans with 81% and East Baton Rouge with 52%. Edwards' 90% in Orleans is particularly impressive given he took 87% of it in 2015 , when he first won election statewide with 56% of the vote.

The movement of suburban areas away from the Republicans is most clearly seen in Jefferson Parish, on the border with Orleans. Edwards won it with 57% of the vote on Saturday. This was impressive. Clinton won a mere 41% of the vote there in 2016. Heck, Edwards took a bare majority of 51% in his 2015 victory.

Why Edwards won

"jungle primary" -- in which all candidates, regardless of party affiliation, ran against each other and the top two advanced ​because no candidate reached a majority. Louisiana's outcome was not just about persuasion -- changing a Republican vote into a Democratic one -- though. Turnout changes may have made the difference between Edwards falling short of 50% in the primary and eclipsing it in the runoff. Specifically, the rise in black turnout. In heavily African American, Caddo, East Baton Rouge and Orleans parishes , turnout was up about 15% to 30% compared to last month's Louisiana"jungle primary" -- in which all candidates, regardless of party affiliation, ran against each other and the top two advanced ​because no candidate reached a majority.

Parishes in the rest of the state saw a lower increase in turnout.

This trend in the early vote data suggested that African Americans were going to make up a larger share of voters in the runoff than they did in October's jungle primary.

The higher black turnout was reminiscent of what occurred in 2017's Alabama's special Senate election. Large turnout from African Americans helped put Democrat Doug Jones over the top in that election . The same could probably be said about Edwards in Louisiana.

One key to turning out black voters is to not merely rely on Trump as a foil. The fact is that Edwards won in Louisiana not because of Trump but because Edwards has been a popular governor with an approval rating north of 50%. He had a strong appeal to the black community in particular.