The battle for the Democratic nomination for the U.S. Senate seat is beginning to heat up as a sitting Columbus councilor has endorsed former Mayor Teresa Tomlinson’s opponent.

Councilor Jerry “Pops” Barnes has thrown his support behind Tomlinson’s primary opponent, Jon Ossoff.

Barnes, a retired Army master sergeant, and nurse served eight years on the city council while Tomlinson was the mayor.

Monday night he attended an Ossoff rally in Columbus and by the end of the week, he was proclaiming his support for the media executive.

“When I went to hear him talk, there were three things that really touched me,” Barnes said. “One he’s connected with the needs of the military. … Even though the VA is stepping up their game, there are certain things that need to done. … The second thing he spoke about was the need for rural healthcare. I’m a nurse. I have gone down into the rural areas and I know that those are necessary. He talked so passionately about both issues. And the third one as a grandfather and great grandfather I am concerned about is we are behind the power curve when it comes to looking out for Mother Earth.”

Barnes says he’s all in going into the May 19 primary.

“He talked about it with such passion that I knew it came from his heart,” Barnes said. “So, that’s what really sold me. That above anything else sold me and I’m on board and I am supporting Jon Ossoff.”

When asked about Barnes’ support of her opponent, Tomlinson told News 3 she respects him. She then pointed out in a text that she had received the support of former Mayor Pro-Tem Evelyn Turner Pugh.

Banes is the only current councilor who has made a public endorsement in the race.

“We’re building a juggernaut grassroots campaign committed to delivering quality health care for every Georgian, investing in our state’s infrastructure, and ending the corruption that’s destroying our democracy,” Ossoff said in a news release Friday morning. “This diverse and growing team will help power two U.S. Senate victories in November, and I’m grateful for their support.”

Tomlinson took exception to that.

“Jon is understandably steeling himself for several endorsements we have coming out next week,” Tomlinson said in a text.

She was in New York for fund-raisers. On Wednesday night, Tomlinson attended a fund-raiser hosted by former Pennsylvania Gov. Ed Rendell in Philadelphia.

In addition to Barnes’ support, Ossoff also announced that Georgia Sen. Emanuel Jones switched his support from Tomlinson to Ossoff.

“To win this race, we need a candidate who can inspire massive turnout among new voters of all ages and backgrounds, and a candidate who can inspire a legion of volunteers to pour their hearts and souls into victory,” Jones said in an Ossoff news release. “To me, that choice is now clear, and that’s why I’m endorsing Jon Ossoff for U.S. Senate.”

Tomlinson told News 3 she respected Jones and hated to lose his support.

Tomlinson and Ossoff are in a crowded Democratic field battling for the nomination and a shot at incumbent Republican Sen. David Perdue.