(CNN) Ted Cruz will be back on the campaign trail Monday -- and will keep jabbing the Republican establishment.

The Texas senator will be campaigning in Colorado for Senate candidate Darryl Glenn. The El Paso County Commissioner is taking on Republican establishment favorite Jon Keyser in the June 28 primary.

Cruz described Glenn as a "constitutional conservative" who will "take on the D.C. establishment."

"I am proud to stand with the grassroots in Colorado supporting Darryl Glenn in his campaign for the U.S. Senate," Cruz said in a statement Friday. "He is a constitutional conservative with the experience to understand what it takes to bring back economic growth and preserve our individual liberties. I am confident he will go to Washington to fight for those values, and he won't back down."

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