California Democrat Katie Porter is going on offense against Republican Rep. Mimi Walters, launching a new television ad highlighting the congresswoman’s support for last year’s GOP tax overhaul and tying her to President Donald Trump. 

Walters, who’s in her second term representing California’s 45th District,  backed the GOP tax measure, which some of her fellow Golden State Republicans opposed because it limited the deductions for state and local taxes. And now Porter is highlighting that vote in a negative spot, which is a joint ad with the Democratic Congressional Campaign Committee.

“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.”

The ad, shared first with Roll Call, will run on broadcast through Election Day. Porter’s campaign declined to disclose the size of the ad buy.

Walters is one of seven California Republicans defending seats that Hillary Clinton carried in 2016, including in Orange County, once considered to be a GOP stronghold. Clinton won the Irvine-based 45th District by 5 points. Inside Elections with Nathan L. Gonzales rates the race a Toss-up. 

Watch: 24 House Ratings Change in Favor of Democrats, One Month Out