In the second Board of Supervisors election in as many months, Johnson County voters elected Democrat Royceann Porter to be their fifth representative on the board on Tuesday, maintaining the board’s entirely Democratic composition.

The victory will make Porter the first African American to hold countywide office. Her candidacy drew some national attention with an endorsement from New Jersey Sen. Cory Booker (D), a potential 2020 presidential candidate.

“I am honored. I am overwhelmed, and it’s just amazing,” she said. “I’m grateful that Johnson County believed in me.”

The special election was held on Tuesday to fill the seat left vacant by first-term Supervisor Kurt Friese, who died on Oct. 26. His term ends in 2020.

Porter ran against Republican Phil Hemingway, a member of the Iowa City School Board. Porter won by a 56-43 percent margin. Porter received 5,444 votes, while Hemingway received 4,167 votes.

Just under 10 percent of registered Johnson County voters cast 9,658 ballots in the election on Tuesday.

Voter turnout was higher than the last special election in 2013 in which 6,113 total votes were cast by 6.7 percent of Johnson County registered voters. In that election, John Etheredge became the first Republican elected to the Board of Supervisors since 1962.

The five-member board oversees county business such as levying taxes, managing the budget, and zoning. Supervisors also manage a number of departments, including the auditor’s office, the sheriff’s department, and emergency services.

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Porter will begin her term on the board on Dec. 26.

Porter has served on numerous boards and committees in the Iowa City area. Most recently, she served on the Iowa City Community Police Review Board and worked as an organizer for the teamsters union. Porter has stepped down from both of those roles to serve on the Board of Supervisors full time.

Porter has outlined homelessness, racial disparity, and improving transportation as some issues she hopes to address during her term. She said her main priority right now is to learn from the other supervisors and listen to community members about the issues they feel matter most.

“My to-do list is to get in there and learn, to see what the top issues are that they’re working on, and continue to help them move Johnson County forward,” Porter said.

Hemingway ran on a platform of rural representation and fiscal responsibility. His priorities also included improved mental-health services, infrastructure, and environmental protections.

Hemingway previously ran in the general election on Nov. 6. He lost to Pat Heiden and incumbent Supervisor Janelle Rettig, receiving 31 percent of the vote.

“I want to thank everyone who had the faith and voted for me during these past two elections,” Hemingway said. “I’d like to thank Royceann for running a positive campaign. I wish her all the best.”