First in The Blast: The conservative Koch political network is endorsing U.S. Rep. Henry Cuellar, D-Laredo, in his hotly contested primary, the first time the operation has backed a Democrat in a federal race.

The endorsement is coming via LIBRE Initiative Action, the nonprofit campaign arm of the network's Hispanic outreach group, which is based in Mission. LIBRE Initiative Action is planning to support Cuellar against his primary challenger, Jessica Cisneros, with direct mail, digital ads and field efforts.

In a memo announcing the endorsement, LIBRE Action senior adviser Daniel Garza praises Cuellar for building consensus on issues such as immigration and trade, finding "allies on both sides of the aisle to push real solutions to real problems." Cuellar has done so, Garza adds, "at considerable political risk."

The endorsement is the latest example of the unconventional outside support that Cuellar, a centrist Democrat, is drawing as Cisneros challenges him from the left. Cuellar is also benefitting from a TV ad campaign by the U.S. Chamber of Commerce, a Republican-leaning group that has not spent seriously on behalf of a Democrat since 2014.

The LIBRE Initiative is one of several groups that engages in politics within the network built by conservative megadonors Charles and David Koch.

Cisneros issued a statement responding to the endorsement, saying it's "no surprise that big Republican money is attempting to bail out Congressman Cuellar as he fails to defend his record to Texas voters."

— Patrick Svitek

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