On Tuesday, former Navy pilot and GOP state Rep. Jake Ellzey defeated fellow Republican Susan Wright 53 percent to 47 percent in a special election runoff to replace Wright's late husband in Texas's 6th CD. Ellzey's victory is an upset, considering Donald Trump endorsed and held a late tele-town hall for Wright. She also had the support of Sen. Ted Cruz and over $1.2 million in outside help from the Club for Growth.

This is the first defeat for a Trump-endorsed candidate in an all-GOP race since Madison Cawthorn beat a personal friend of Mark Meadows in North Carolina's 11th CD last year. And, it will be tempting for Trump antagonists to spin Wright's defeat as evidence of the limits of Trump's influence in his post-presidency. However, there were unique factors in TX-06 that won't be applicable in upcoming GOP primaries.

First, TX-06 wasn't truly a Republican primary. Texas holds its special elections under a Louisiana-style jungle primary/runoff format; meaning Democrats weren't just permitted to cast ballots in the runoff; they probably made the difference for Ellzey — particularly in

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