Tom Perez fought hard three years ago to win confirmation as U.S. labor secretary from a hesitant Senate. But lately he has been answering to another, unofficial title almost as frequently.
"Potentially our next vice president," a union official roared into a microphone as the Marylander took a stage recently on Capitol Hill.
With the primaries over and attention now focused on the general election in November, talk of Perez joining presumptive presidential nominee Hillary Clinton on the Democratic ticket has persisted, even as other names have come and gone.
The idea has drawn praise from labor and unease from some business groups.
Perez, a former head...