AUSTIN (KXAN) — Starting Thursday, Austin voters will have their chance to elect the city’s next mayor in a runoff race between Sen. Kirk Watson and Rep. Celia Israel.

While both have served several terms at the state level, neither is unfamiliar with Austin politics. Watson previously served as mayor from 1997-2001, while Israel’s previous city leadership roles included positions on Austin’s Environmental Board, Police Monitor Board, 2011 Bond Advisory Commission and the Robert Mueller Advisory Commission.

Whoever is elected mayor will operate under a council structure that wasn’t in place during each’s last time in city government.

Prior to 2012, Austin City Council comprised six at-large council seats serving alongside the mayor. Voters approved a resolution to reformat council in 2012 to a 10-1 structure, a format with one mayor and 10 council districts. Mayor Steve Adler was the inaugural mayor elected to serve under council’s 10-1 makeup.

“[That] means that the mayor has to get along with a lot more different voices,” said Brian Smith, a political science professor at St. Edward’s University. “Under the old council system, it was much smaller councils, so it’s easier for everybody to sit around a coffee table and discuss things — now you do need a room. So a good mayor is going to be able to navigate many more voices.”

Historically, Austin’s previous six at-large seats meant candidates from a small handful of prominent zip codes had a stronger investment in their interests. With the 10-district format, the structure adds not only more voices but more diverse voices representing a wide range of neighborhoods and constituents at the dais.

“The mayor now has to deal with the different issues that weren’t represented in the city, the different parts of the city that weren’t represented,” he added. “When we think of the old Council, it was dominated by two or three zip codes, all within a clustering of downtown. Now when we think about the new council, it represents all of the city, and with that means new issues and new voices.”

With both having extensive political careers, Smith said the challenge here isn’t about which candidate has the experience needed to win. Rather, he said it’s who has the personality and capability to work with a wide range of council voices to get policies through.

“The governing experience for both candidates is going to be a huge asset no matter how you vote,” he said. “But you have to look and say, ‘who do you think is going to be able to really push that vision of the city?'”

For Watson, relearning the new council structure under a larger city than he previously led is a switch up, Smith said, but it’s also where his experience in both local and state positions can serve him. Similarly, Smith added Israel’s familiarity with the region through her Texas House District service are advantageous to her campaign.

“The best mayor is going to be the one that is going to be able to work with the larger council, the city manager and really show the city of Austin to be what it is a great city,” he said.

KXAN is hosting a debate between Israel and Watson Thursday at 9 p.m. The debate will air on KXAN, the CW Austin and on KXAN.com.

Early voting in Austin’s mayoral runoff begins Thursday and runs through Dec. 9. Election Day is Dec. 13. Whoever is elected mayor will only serve a two-year term after Austin voters opted to move mayoral elections to presidential election years.