Portland City Commissioner Chloe Eudaly held a narrow lead over challengers Mingus Mapps and Sam Adams late Tuesday night.

At 11 pm, Eudaly had 30.22 percent; onetime political science professor Mingus Mapps, 28.71 percent; and former Portland Mayor Sam Adams, 28.22 percent.

Most of the ballots have been counted: 43 percent of those registered to vote in Multnomah County, in a race where turnout isn't expected to be much higher than 50 percent. That means Eudaly's lead should put her in a November runoff.

Mapps, a first-time candidate, held a 756-vote lead over Adams, who served as Portland mayor from 2009 to 2013. That's probably a big enough advantage to put Mapps in the runoff as well.