I don't understand why not just used one "have to". To me, "have to" is redundant in "had to have to".

Context: A few weeks later, I’d be tested like that again. I was in Clarksville in the Arkansas River valley with my twenty-two-year-old county leader, Ron Taylor, who was from a prominent political family and politically wise well beyond his years. He took me out to the county fair to see the county sheriff, whose support Ron said we had to have to carry the county. We found him at the rodeo grounds, holding the reins of a horse. The rodeo was about to begin with a parade of horses marching around the arena. The sheriff handed me the reins and told me to join the parade and I’d be introduced to the crowd. He promised that the horse was well
behaved. I was wearing a dark suit and tie and wing-tipped shoes.
'Whose support Ron said we had to have in order to carry the county' = whose support we needed in order to get the most votes in the county.