Another Democratic candidate jumped into the race Monday to take on Texas Republican Sen. John Cornyn — the latest sign that Democrats could face multiple contested primaries for Senate seats they think they can win in 2020.

Despite the prospect of intramural warfare, Democrats say they aren’t fretting yet that the primaries could endanger efforts to win control of the Senate, which will likely go through Texas, Colorado and other states.

“I’m not concerned because it’s so early,” said Katie Farnan, a leader of Indivisible Front Range Resistance in Colorado, where ten Democrats are vying to take on first-term GOP Sen. Cory Gardner.

“If you come back in 2020 at the top of the year, I’m going to have a different answer,” Farnan said.

Primaries can be early tests for candidates by helping them work out the kinks before a competitive general election. But primaries can also drain resources and damage the eventual nominees with bruising political attacks.