Cllr Newmark was re-elected to his Borehamwod Cowley Hill ward within Hertsmere Borough Council on Thursday, alongside two other Labour candidates.
Richard Butler and Michelle Vince won 879 and 866 votes, respectively, while Cllr Newmark received 733 votes.
Cllr Newmark has been the leader of the Hertsmere Labour group since October 2017.
He also came 1,657 votes short of unseating Finchley and Golders Green MP Mike Freer in the 2017 general election.
Elsewhere in Hertsmere, Jewish Conservative candidate Sam Lawrence, 21, became the borough’s youngest elected councillor. He is a second year politics student at the University of Nottingham.
He posted to Facebook: “It’s been a privilege to work with such a wonderful team on the campaign whilst learning about the most pressing issues that our constituents face.
“It may have been a rough night for the party nationally, but the most important thing now is to get the job done that we were put here to do.
“Congratulations to all who ran and thank you to all who voted for me!”
