Texas Elections 2018 More in this series

El Paso County Judge Veronica Escobar has officially started her run for Congress.

Escobar, a Democrat, submitted paperwork Friday to the Federal Election Commission to begin a campaign for Texas' 16th Congressional District. U.S. Rep. Beto O'Rourke, D-El Paso, is giving up the seat to run for U.S. Senate in 2018.

Escobar is expected to make the campaign official Saturday, when she's invited supporters to a "special announcement" in El Paso.

Escobar, who is close with O'Rourke, was almost instantly seen as a potential candidate to replace him when he announced in March he would challenge U.S. Sen. Ted Cruz, R-Texas. She already has his backing in her bid for Congress.

"Beto has really done an outstanding job of raising the bar for this seat and making the border a topic of national conversation in a very positive and productive way," Escobar said in an interview, describing her decision-making process. "That was an important component."

Escobar said she was also driven to run for Congress out of concern for the impact decisions made under President Donald Trump are having on El Paso, Texas' largest border city. There's a "very dark cloud over our nation right now," she said.

In recent weeks, Escobar had also received support from a draft effort by a national group, the Latino Victory Project. If elected, Escobar would become the first Latina member of Congress from Texas.

A number of Democrats are already running for the solid-blue 16th District, the most prominent of which is Dori Fenenbock, the former El Paso school board president. She's been campaigning for the seat for months through an exploratory committee, and she has already built a $329,000 war chest.

On Friday, Fenenbock resigned from the school board, saying she has been "called to other service at a critical time in our history" and does not want it to be a distraction. A day later, her campaign promised a "formal announcement" on Sept. 9.

Asked about Fenenbock, Escobar said she is thrilled so many women are running for the seat — at least one other is — and believes contested primaries are healthy for the party. But she also said El Pasoans will see a "very clear distinction" on policy between herself and Fenenbock, noting that the city has a history of electing "strong Democrats," and she doubts that will change in 2018.

Escobar's term as county judge ends in December 2018, and she had already announced she would not seek re-election. Under state law, county officials like Escobar automatically resign when they announce they're running for another office with more than a year and a month left in their current term. But Escobar can remain on the job until the El Paso County Commissioners Court picks someone to finish her term, she said.

At their Monday meeting, El Paso County commissioners are scheduled to "discuss and take appropriate action to fill the vacancy of the El Paso County Judge," according to an agenda that was updated Friday. Escobar she has "an idea" of whom she would like to replace her but declined to identify the person.