An area represented by Republican Rep. Darrell Issa for years could find itself with an influx of blue voters if Prop. 50 passes.

According to California Vehicle Code, drivers must stop at a red light before the crosswalk or intersection. Drivers “shall remain stopped until an indication to proceed is shown,” the law says.

U.S. Transportation Secretary Sean Duffy is warning that he is about make good on a threat to revoke millions in federal ...