Those percentages are in line with the drubbing just north of Louisiana in Arkansas.
Cotton (R) won by 57% over Pryor (D-Incumbent) 39%.
Most of the polls leading up to the election showed them almost even. A few times, they showed Cotton up by about 7%, then near even.
The week before the election, the University of Arkansas released results of a poll that showed Cotton ahead by 14%. Few commentators took that poll seriously. Ironically, it was closer to the final result than the other polls.
and don’t forget the statewide races in next-door Texas where Democrats failed to hit the 40% mark.