AUSTIN (KXAN) — Austin City Council Member Greg Casar made it official Thursday — he’s running for Congress.

Casar made the announcement via Twitter with a video post.

“A better world is possible if we fight for it,” his Twitter post said. “That’s why I’m running for Congress. To stop the attacks on working Texans. To win Medicare for all, good jobs, affordable housing and a strong democracy.”

Casar, a Democrat, announced Oct. 19 that he put together an exploratory committee to look into a potential run for the newly-drawn Congressional District 35. Current Rep. Lloyd Doggett plans to vacate the seat to run for the spot in District 37, another district with new lines.

The new District 35 encompasses most of Travis County east of Interstate 35, but snakes south down the freeway through Hays and Comal counties, all the way into Bexar County and parts of San Antonio.

In the video that has both English and Spanish subtitles, Casar said while progressives have made some change in Texas, “our biggest challenges are still ahead.”

“I believe that working families, from Bexar to Hays to Comal to Travis County, deserve a progressive leader who will always fight and deliver for reproductive rights, good jobs, Medicare for all and a better Texas,” he said. “That’s why I’m running for Congress, because this is our fight, our future.”

Casar won a seat on the Austin City Council in 2015 and represents District 4, which straddles I-35 in central Austin. His current term on council expires in 2025. He previously worked as the policy director for the Workers Defense Project, an advocacy organization for low-wage, immigrant workers in the Texas construction industry.

State Rep. Eddie Rodriguez, currently representing Texas House District 51, filed paperwork Thursday to also run for office in the district.