A new internal poll shows California Rep. Mimi Walters with a 50 percent share of the vote, leading Democratic challenger Katie Porter by 4 points. 

The incumbent’s 50-46 lead is within the poll’s +/-4.9% margin of error.

Porter, a University of California, Irvine professor, hopes to unseat Walters, who is seeking her third term in the 45th District. Walters’ is one of seven districts won by Hillary Clinton in 2016 currently being represented by Republican legislators. Clinton won the district by 5 points.

The poll ran from October 14 through October 17, just as Porter launched a new television ad hitting Walters for her vote in favor of last year’s GOP tax bill.

“The Walters-Trump tax plan gives away trillions to big corporations and Washington special interests, adds trillions more to the national debt, and threatens deep cuts to Medicare and Social Security,” the narrator says in the 30-second spot. “And Walters and Trump raised taxes on Orange County families to pay for it.”

Walters’ campaign consultant Dave Gilliard called the congresswoman a “tax-fighter and government reformer” in a statement accompanying the poll.

Public Opinion Strategies conducted the poll, surveying 400 likely voters by phone evenly split between cell phones and landlines.

Inside Elections with Nathan L. Gonzales rates the race for the 45th District a Toss-up. 

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