(CNN) In another striking loss for Republicans, Orange County US Rep. Mimi Walters on Friday conceded to her Democratic opponent Katie Porter, the one-time protégée of Elizabeth Warren who was once deemed by critics to be too progressive to win the Republican California stronghold.

Walters, a former stockbroker who rose quickly after her 2014 arrival in Washington, was well liked in her district as a business oriented, anti-tax conservative.

But the drag of Donald Trump's rhetoric in her increasingly diverse district proved to be too much to allow her to hold her seat. Porter ran a disciplined campaign against her, relentlessly casting Walters as a rubber stamp for the Trump administration.

With Walters' concession, Democrats have now picked up a net gain of 34 seats in the House. Six races remain to be called by CNN, and Democrats lead in five of them. All of the uncalled districts are currently held by Republicans.

Walters was also hurt by her support for the Republican tax bill, which altered state and local deductions at a huge cost to California homeowners — particularly in the wealthy enclaves of Orange County. That, paired with the anger toward Trump among college-educated women, took a heavy toll on Walters in the well-educated areas of Irvine, the heart of her district.

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