*Correction appended

HOUSTON — Accusing Republicans of a systematic effort to undercut voter access to the ballot box, Hillary Clinton called for expansive reforms to U.S. election laws in a speech Thursday. The front-runner for the 2016 Democratic presidential nomination also called out four potential Republican opponents — including former Texas Gov. Rick Perry — for what she called a "crusade against voting rights."

“We have a responsibility to say clearly and directly what’s really going on in our country, because what is happening is a sweeping effort to disempower and disenfranchise people of color, poor people and young people," said Clinton. Speaking at historically black Texas Southern University, the former secretary of state criticized states like Texas for tightening election laws through voter identification and preregistration requirements.

“Since the Supreme Court eviscerated a key provision of the Voting Rights Act in 2013, many of the states that previously faced special scrutiny because of a history of racial discrimination have proposed and passed new laws that make it harder than ever to vote,” she said.

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The 2013 Texas voter ID law, considered the toughest in the nation, was signed by Perry, who launched his second bid for the White House near Dallas a few hours before Clinton took the stage in Houston.

Clinton took aim at Perry directly Thursday — along with fellow current or former Republican governors Chris Christie of New Jersey, Scott Walker of Wisconsin and Jeb Bush of Florida.

"Republicans are systematically and deliberately trying to stop millions of American citizens from voting. What part of democracy are they afraid of?” she said.

To help cut down on long lines and generally make it easier to cast a ballot, Clinton proposed requiring at least 20 days of in-person early voting in every state, including on weekends and evenings. She also called for universal automatic voter registration of U.S. citizens when they turn 18.

In Texas, state law now allows in-person early voting for two weeks, and weekend voting is not always guaranteed, depending on the size of the county and other factors.

Clinton was at Texas Southern to receive its first Barbara Jordan Gold Medallion, a leadership award given in memory of the groundbreaking former Texas congresswoman and civil rights champion who is an alumna of the university.

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During her roughly 30-minute remarks, Clinton said she first met Jordan while working as a young lawyer for the U.S. House Judiciary Committee.

“Like every woman who has run for national office in this country in the last four decades, I stand here on the shoulders of Barbara Jordan,” she said.

Clinton also recounted a period in 1972 she spent in Texas registering voters in the Rio Grande Valley, who she said were "a little wary of a girl from Chicago who didn’t speak a word of Spanish.”

The candidate did not take any questions from reporters at the Texas Southern speech, which was her only public appearance during a packed two-day swing through Texas.

The trip began with an event at San Antonio’s Club Giraud organized by Henry R. Muñoz III, a top Democratic bundler who became the finance chairman of the National Democratic Committee in 2013. On Wednesday night, she was hosted by Dallas personal injury lawyer Frank Branson.

On Thursday morning she attended a private fundraiser at the Austin home of Suzanne and Marc Winkelman.

Her time in Texas was set to wrap up Thursday afternoon with a final fundraiser in Houston at the home of businessman Masoud Ladjevardian and his wife, Sima, a lawyer.

Correction: This story originally misidentified Frank Branson as Jack Branson.

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Disclosure: Suzanne and Marc Winkelman are major donors to The Texas Tribune. A complete list of Tribune donors and sponsors can be viewed here.

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