In the history of the Obama campaign’s storied analytics operation, the effort to model the results live on Election Day, before the votes were tallied, was undoubtedly a low point. “That was the worst 12 hours of my life,” said David Shor, a senior data scientist at Civis Analytics who was in the “Cave” — the Obama analytics boiler room — on Election Day of 2012. By late morning, some in the Obama team concluded that President Obama was losing Ohio. This year, Election Day could be the wor...