AUSTIN, Texas — The Texas AFL-CIO will not endorse U.S. Rep. Beto O'Rourke, D-El Paso, in his campaign to strike down U.S. Sen. Ted Cruz, R-Texas, after O'Rourke did not appear at its convention this weekend in Austin.

On Sunday, the labor group released a list of statewide candidates it had decided to support, and it offered no endorsement in the Senate race. The group's constitution requires two-thirds support to endorse a candidate, and O'Rourke wasn't on the list.

"I think that our members don’t like to be just taken for granted," Texas AFL-CIO president Rick Levy told The Texas Tribune.

"Just because you have a D or an R behind your name doesn’t determine whether you’ll have our support."

According to the Tribune, O'Rourke said that his campaign had tried to find a way for him to make it to the convention, but he was unable to attend because he had previously scheduled campaign events elsewhere in the state. He ended up canceling those events, though, because he was stuck in Washington, D.C., over the weekend due to the government shutdown.  

O'Rourke added that the AFL-CIO gave him a 100 percent rating on his voting record in 2016, and his lifetime score is 95 percent. Cruz, on the other hand, got 67 percent in 2016 and 12 percent overall.   

"It’s on me to further develop and strengthen those relationships and if anybody feels they’re being taken for granted, that’s on me to fix," said O'Rourke, who faces two little-known opponents in the Democratic primary for U.S. Senate. "I'm just going to do a better job reaching out and trying to work with the members of the AFL-CIO."

The AFL-CIO could still change its mind and offer a bid of support to O’Rourke. It said Sunday its "endorsements are subject to updates based on primary and runoff election results and other factors."

The labor group did however, offer an endorsement to Lupe Valdez, former Dallas County sheriff, over Andrew White, the son of late Gov. Mark White, in the Democratic gubernatorial primary. 

The Texas AFL-CIO is a state labor federation consisting of approximately 237,000 affiliated union members.