Why DeSantis currently holds an edge over Haley
With 83 percent of the expected vote now reporting, DeSantis holds about a 2-point lead over Haley for second place, 21.3 percent to 19.0 percent. That could change, but it's not hard to see why DeSantis is in that position: He's got a narrow lead over Haley in the places where we'd expect Haley to perform best. In six populous and highly educated counties that form substantial parts of the Des Moines, Cedar Rapids, Iowa City and Davenport areas, DeSantis leads Haley by a little over 2 points, 26.8 percent to 24.6 percent. These are places that Haley needed to perform especially well in — polling has shown she tends to do better among college-educated voters — but instead she's running slightly behind DeSantis across all six. Haley actually has a slim lead over DeSantis in five of these places, but critically DeSantis is doing a little better than Haley in Polk County (home to Des Moines), which will have far and away the most votes of any place tonight.
—Geoffrey Skelley, 538