He garnered 56 percent of the vote to defeat Michael Kiernan and Abshir Omar, according to unofficial results from the Polk County Auditor’s Office.
Mandelbaum will replace Christine Hensley in January. Hensley has served on the Des Moines city council for 24 years. She did not run for re-election.
“It was a real hard-fought campaign,” Mandelbaum told the Des Moines Register. “We had three strong candidates that were issue-focused, and we’re proud of the race we ran.”