Former Colorado state Sen. Mike Johnston (D) suspended his Senate campaign against Sen. Cory Gardner (R-CO) on Tuesday to avoid running against ex-Gov. John Hickenlooper (D), a former 2020 presidential candidate who’s now gunning for Gardner’s seat as well.

“I think [Hickenlooper’s] entrance required this to be a very different kind of race and required a negative race that’s not one that matches my values and how I would want to lead,” Johnston told the Denver Post.

The Colorado Democrat said that an ugly Democratic primary process would “break a lot of long-standing relationships in the state” and help Gardner and Senate Majority Leader Mitch McConnell (R-KY) maintain Republican control of the chamber.

After consistently polling at less than 1 percent, Hickenlooper dropped out the presidential race in August and announced his bid for Senate.

“I’m not done fighting for the people of Colorado,” he said in his announcement video.

According to the Denver Post, Hickenlooper is the highest polling candidate out of the 11 Democratic candidates aiming to unseat Gardner.