San Antonio Councilwoman Elisa Chan has submitted her resignation letter to the city council.
Chan's last day as District 9 councilwoman will be Oct. 18.
Chan said she will challenge District 25 State Sen. Donna Campbell in the March GOP Primary.
In September, Chan told KSAT she planned to work logistic issues with her new senate campaign.
The deadline to file is Dec. 9.
Chan made headlines recently following the leak of secretly recorded remarks she made about homosexuals during the run-up to the city's then-proposed non-discrimination ordinance. Chan has represented District 9 since 2009.