That would be the 15% reporting. It’s more about their understanding of which precincts have reported, how much population they represent (urban or rural precincts), and how those precincts would need to break down for one candidate or the other. Then they match it to what report is coming in and make the call if it fits (if Sherman’s strongest precincts were coming in and he was already losing there or underperforming significantly, that’s the kind of red flag they would look for to make an early call)