Portland mayoral candidate Mark Dion shakes hands outside an Ocean Avenue polling station on Election Day, Tuesday. Credit: Troy R. Bennett / BDN

Portland City Councilor Mark Dion held a big lead after the first round of voting for the city’s open mayoral seat on Tuesday night, but two of his more progressive opponents could still win the ranked-choice voting race.

Dion, a former Cumberland County sheriff and state lawmaker, won 39.6 percent of votes to 26.4 percent for Councilor Andrew Zarro and 21.9 percent for Councilor Pious Ali. Former Councilor Justin Costa got 7.9 percent, while political newcomer Dylan Pugh got 4 percent.

The race will be decided in a ranked-choice voting tally at 10 a.m. Wednesday. Pugh will be eliminated and the second choices of his voters will be reallocated to the remaining candidates. That process will continue until one candidate wins a majority.

Mayors in Maine’s largest city have struggled to cement themselves in the full-time elected position established in 2011. The first mayor was ousted by the second in 2015. Ethan Strimling was then defeated by Kate Snyder in 2019. She declined to run for a second term after presiding over the city’s response to the COVID-19 pandemic.

The dueling homelessness and housing affordability crises have marked this year’s election. Dion has emphasized public safety when discussing the first issue. This week, he was the only candidate to criticize a councilor’s plan to allow camping in parks over the winter.

It was only one of the issues that has put Dion, who was a progressive Democrat in the Maine Legislature, to the right of the other candidates in the race. He was also the only one to oppose raising Portland’s minimum wage even after it rises to $15 hourly early next year.

Zarro focused his campaign largely on housing, setting an ambitious goal of building 12,000 new units in the city. Ali pitched himself as a convener, defending Gov. Janet Mills in one debate after Dion said her administration needed to do more to help Portland provide services to an influx of asylum seekers.

Michael Shepherd joined the Bangor Daily News in 2015 after time at the Kennebec Journal. He lives in Augusta, graduated from the University of Maine in 2012 and has a master's degree from the University...