Voters chose between Chula Vista Mayor John McCann and Imperial Beach Mayor Paloma Aguirre. Polls closed at 8 p.m.

Casting mailed ballots remained popular among voters in last year’s presidential election, even as President Donald Trump has tried to undercut the process through a wide-ranging executive order.

Both supervisor candidates, Paloma Aguirre and John McCann, pushed Saturday to reach undecided South County voters.