If the race were head-to-head, the poll reveals Trump besting DeSantis by a 2 to 1 margin. Overall, Mr. Trump led Mr. DeSantis 54 percent to 17 percent. Below those lopsided top-line figures were other ominous signs for Mr. DeSantis. Republicans who described themselves as “very conservative” favored Mr. Trump by a 50-point margin, 65 percent to 15 percent. The poll also found that in a “hypothetical one-on-one race against Mr. Trump, he would still lose by a two-to-one margin, 62 percent to 31 percent, the poll found.