It will take another month for Denver's next mayor to be named.
Assuming current election results hold up, incumbent Michael Hancock will face neighborhood development consultant Jamie Giellis in a head-to-head runoff election to decide who will lead Denver for the next four years.
No candidate for mayor received more than 50 percent of the vote Tuesday, which triggers a runoff between Giellis and Hancock, the top two finishers, if the results hold. About 155,000 people cast ballots Tuesday, or about 37 percent of registered voters.
As of 1 a.m. Wednesday, about 39 percent of voters chose Hancock, the eight-year, two-term incumbent from Denver.
About 26 percent picked Giellis, a political newcomer who played a key role in creating the RiNo Art District in Five Points, which has seen transformational development over the last several years.
Hancock told his supporters that efforts for a runoff start Wednesday morning. Giellis was not as quick to confirm a runoff, but claimed the relative victory eventually.
"I think to see the numbers where they came in, it was shocking to a certain extent, because the margins between the candidates were so wide, but ultimately it was right where we had thought we would be, and it's a great position for us to be in," Giellis said from her campaign party at the Ramble Hotel.
Hancock took the stage during his election night party at EXDO Events Center after he learned this political game would likely require extra innings. He congratulated Giellis and told supporters that the runoff campaign starts tomorrow.
"We didn't lose anything tonight," Hancock said. "We get another chance to prove to voters and to Denver that we're moving in the right direction."
A runoff will take place Tuesday, June 4.
Lisa Calderón, a criminal justice professor and advocate, sits in third place with about 18 percent of the vote. She eventually conceded Wednesday afternoon.
When asked if she would throw her support behind another candidate in the runoff, Calderón said, "That is not my intention at this time."
Penfield Tate received almost 15 percent of the vote. He could not be reached for comment Tuesday night, but said before election results trickled in, "We've worked very hard and we're looking forward to being in the runoff."
Artist and homeless advocate Kalyn Rose Heffernan earned about 2 percent, while protest candidate Stephan "Chairman Seku" Evans won less than 1 percent.
A Giellis victory would mean a woman would run the city for the first time since its founding in 1858.
During her campaign, she committed to reining in development, exploring building a streetcar network in Denver and providing a better network of services for people without homes.
If Hancock wins, he will continue a tenure that began in 2011. His administration has ushered growth and development into neighborhoods in various pockets of the city, including the expansion of Denver International Airport and the widening of Interstate 70 through Elyria, Swansea and Globeville.
Denver has experienced unprecedented economic growth with him at the top, but the high cost of living has pushed residents out, too. During his campaign, he committed to increasing Denver's affordable housing stock and cutting down on the number of people experiencing homelessness.
A heavily favored Hancock blamed the outcome on the number of "viable candidates" in the race that he had to contend with, and newcomers who did not vote.
"This is a city where many people who live in this city built and created it, so that you can find a place that's desirable," Hancock said. "We're glad you're here but now we've all got to participate." In a dig at Giellis's voting record, he added: Everybody must vote, including Jamie Giellis."
Giellis, too, said winning will be about turning people out in a runoff.
"It's gonna be all about getting out the voters again, continuing to build the bridges with those people who have been divided in this campaign," Giellis said.
Voter turnout for runoff elections is typically lower than general races, so the candidates will be scrapping for votes, said Robert Preuhs, a professor of political science at Metro State University who studies urban politics.
"My sense is that Hancock and Jamie are gonna go out and stump for votes and find pockets of people who voted for Tate and Calderón," Preuhs said. "I cant imagine that Calderón or Tate voters would do much more than split their votes (for Hancock), and that's if people even turn out to vote.
Denver Elections Division will mail ballots May 20. The candidate whose name appears first may have the best chance of winning, if history is a guide. Since 1999, 70 percent of runoff elections went to the candidate at the top of the ballot.
While the mayoral election grabbed headlines, two ballot initiatives seemed to drive voters to the polls.
Reporters Esteban Hernandez, Michael Elizabeth Sakas and Kevin Beaty contributed to this article.
