No. The Whitest parts of the state were Stennis' best.
What would be your guess as to the percentage of the white vote Stennis received?
Highly dependent on the region. Probably over 70% in the Northeast and around the Coast, maybe 40% in the Delta, and 35% in Metro Jackson?
This is definitely more an urban/rural divide than a racial one. Black turnout was especially high in the Delta that year due to a competitive House race, but I suspect a lot of Black voters there may have under-voted or voted for Barbour. Barbour himself estimated he got 20-25% of the Black vote in 1982.
Which, if we assume the Black vote in 30% of the electorate and Barbour wins 20% of them...
30*0.20 = 6% of the electorate is Black Barbour voters, which means Barbour has to win about 42% of the 70% White electorate to get to 36% of the statewide vote? I may be overestimating the size of the Black electorate (or Barbour's performance among them), so that would actually improve his numbers with White voters.