As early voting breaks records across the U.S., political analysts and campaigns are reviewing reams of data on the voters, looking for clues to key questions: Who is voting? And who is winning? On one level, the answers can be simple. Registered...

More than 17 million Americans have already cast ballots in the 2020 election, a record-shattering avalanche of early votes driven both by Democratic enthusiasm and a pandemic that has transformed the way the nation votes. The total represents 12%...