Her statement drew harsh criticism from Governor Abbott who said, "sanctuary city policies like those promoted by your recent decision to implement your own case-by-case immigrant detention plan will no longer be tolerated in Texas".
Valdez said she looks forward to spending the next year speaking with Texans about issues such as healthcare and immigration, specifically addressing the fear many undocumented immigrants have of deportation.
Valdez made the announcement at the Texas Democratic Party Headquarters in downtown Austin. "I believe good government can make people's lives better, and I intend to do just that", said Valdez in a statement Wednesday morning.
Abbott, now seeking a second term, often polls as the state's most popular elected official. Andrew White, the son of late Gov. Mark White, has been exploring a run for weeks and is set to announce his campaign Thursday in Houston. With five days left before the filing deadline, Valdez joins six "little known Democrats" in running for the top spot on the ticket, the Tribune wrote.
In the fight against Abbott, who has months of preparation, a $41 million war chest and a Republican incumbency to boost him along, Valdez will be a severe underdog should she secure the Democratic nomination.
"I think we're going to raise whatever money's necessary".
In Valdez, 70, Democrats are now putting up a far different candidate: a one-time migrant worker and Army veteran with more than 40 years in law enforcement.
Abbott now remains unopposed going into the Republican primary.
Abbott's campaign did not have any immediate reaction to Valdez's candidacy.
Abbott declined comment, but announced that he'd won the Dallas Police Association Pac's endorsement.
Valdez will have other challengers in the Democratic gubernatorial primary, including Dallas businessman Jeffrey Payne, former congressional candidate Tom Wakely of San Antonio and former Balch Springs Mayor Cedric Davis.
Valdez, a former senior agent for the U.S. Customs Service in the Department of Homeland Security, addressed the Democratic National Convention in Philadelphia a year ago but she is largely unknown outside of North Texas.
Abbott and Valdez are not unfamiliar with one another.
Valdez's actions and those of fellow sanctuary sheriff, Travis County Sheriff Sally Hernandez, led to the creation and passage of Texas' SB4 Sanctuary City Law.
If she wins her Democratic primary, it won't be the first time she and Governor Greg Abbott will have clashed.