Super Tuesday is more than just a make-or-break moment for the Democratic presidential candidates -- it’s also a huge primary day for congressional candidates in a half-dozen states across the country.

Three well-known Republicans – former Sen. Jeff Sessions in Alabama, former Rep. Pete Sessions in Texas and former Rep. Darrell Issa in California – are seeking to stage a political comeback on Super Tuesday to return to Congress.

SUPER TUESDAY GUIDE: THE STAKES, THE STATES AND MUCH MORE

The election will also be judgment day for Jessica Cisneros, a 26-year-old progressive who is trying to pull off an Alexandria Ocasio-Cortez type of upset win over incumbent Democrat Rep. Henry Cuellar in Texas.

On Super Tuesday, 14 states will cast votes in the presidential election and award a third of the delegates to the Democratic National convention. Six of them will also have down-ballot federal primaries that will slash the field of candidates in California, Texas, Alabama, Arkansas, Colorado and North Carolina.

Here’s a look at some high-profile races to watch.

ALABAMA SENATE

Former Attorney General Jeff Sessions is seeking to reclaim the Senate seat he had for 20 years and faces a tough primary fight against Tommy Tuberville, the famed former Auburn University football coach, and Bradley Byrne, a Republican congressman.

The winner will become Republicans' best bet to pick off an accidental blue seat.

The state's Democratic senator, Doug Jones, squeaked out a victory in the solidly red state in the 2017 special election over GOP nominee Roy Moore, who was widely disavowed for allegations of past sexual misconduct with minors but had retained Trump’s endorsement.

Sessions was the first senator to endorse Trump for his 2016 presidential bid and was rewarded with the attorney general position, a job he called the most meaningful of his life.

But Trump soured at Sessions when he recused himself from the FBI Russia probe that gave way to the appointment of Special Counsel Robert Mueller and called Sessions the “biggest mistake” of his presidency.

Sessions resigned at Trump’s request in November 2018. He launched his political comeback a year later in a campaign ad that was mocked as a hostage video as Sessions stressed he didn’t write a “tell-all book” or say a “cross word” about Trump since he was ousted.

Meanwhile, Tuberville has Trump's name on the back of his campaign bus and says “God sent us Donald Trump” in his television ad.

The primary race also includes Moore, businessman Stanley Adair and state Rep. Arnold Mooney.

The election is likely headed for runoff between the top two finishers. The winner will face Jones in November.

NORTH CAROLINA SENATE

Cal Cunningham is among a crowded field of Democrats seeking the party’s nomination in North Carolina to face incumbent GOP Sen. Thom Tillis in November – a seat Democrats are eyeing as a pickup opportunity.

Cunningham is an Army veteran of Iraq and Afghanistan, businessman and former state senator. He’ll face fellow Democrats Erica Smith, Trevor Fuller, Atul Goel and Steve Swenson on Tuesday.

Tillis is facing GOP primary challenges from the right who accuse the first-term senator of not fully supporting Trump or representing the conservative base.

Republicans Paul Wright, Larry Holmquist and Sharon Hudson are fighting to beat Tillis for the Republican nomination.

Republicans currently hold a 53-47 seat majority in the Senate. Democrats need to pick up a net of four seats to retake the Senate and they’ve targeted North Carolina as a state to flip in November.

TEXAS SENATE

A large crowd of Texas Democrats are seeking the party’s nomination to face incumbent GOP Sen. John Cornyn in November.

The winner hopes to achieve the ultimate Democratic achievement of flipping Texas blue – just two years after former Rep. Beto O’Rourke came close to beating the other Texas Republican, Sen. Ted Cruz.

MJ Hegar, a Harley-Davidson riding Air Force veteran, has been the Democratic front-runner in fundraising and polling. The centrist Democrat has the backing of the Democratic Senatorial Campaign Committee.

She faces state Sen. Royce West of Dallas, former congressman Chris Bell of Houston, former Houston City Council member Amanda Edwards and Cristina Tzintzún Ramirez, a progressive organizer from Austin.

If Hegar fails to get above 50 percent of the vote Tuesday, the race will head into a two-person run-off on May 26.

CALIFORNIA 50TH CONGRESSIONAL DISTRICT

Darrell Issa, the former combative House Oversight Committee chairman who took on the Obama administration, is seeking to return to Congress in the 50th congressional district. The wealthy car alarm magnate served in the House for 18 years and announced in 2018 he wouldn’t seek re-election in his 49th congressional district. The open seat flipped blue to Democrat Mike Levin two years ago.

Now Issa is running in a neighboring district that is solidly red. He's locked in a nasty, expensive race with Carl DeMaio, a former San Diego City Councilman and radio talk show host.

The winner will succeed former Rep. Duncan Hunter, who resigned from office in January after pleading guilty to a single count of conspiracy to misuse at least $150,000 in campaign funds for personal expenses. Hunter, whose dad was a congressman before him, will be sentenced March 17.

DeMaio, the first openly gay man on the San Diego city council and well-known political commentator, and Issa have slugged it out over who is more loyal to Trump. Both have accused each other of lying.

Trump has not endorsed in the race.

The San Diego Union-Tribune, the largest local newspaper, is fed up with both candidates. It said a "general election without this pair’s vitriol would be a blessing," and endorsed Republican state Sen. Brian Jones and Democrat Ammar Campa-Najjar, saying both are more focused on serving the district where they have long lived. Issa and DeMaio don't live in the district.

The top two finishers regardless of party will compete in the general election in November.

TEXAS 17TH CONGRESSIONAL DISTRICT

Pete Sessions, who served in the House of Representatives for 11 terms before losing his seat to a Democratic challenger in 2018, is running to return to Congress -- but in a different district that is safely red.

Sessions says he has “unfinished business” in Congress: removing Nancy Pelosi as House speaker, helping Trump build the border wall and balancing the federal budget with spending cuts rather than new taxes.

Sessions lost in 2018 to Democrat Colin Allred, a former NFL player and a civil rights lawyer, in his Dallas area 32nd congressional district. Now he is one of 11 Republicans vying for a vacant seat in Waco from the retiring Rep. Bill Flores.

Flores has endorsed Waco businesswoman Renee Swann.

Other candidates are Elianor Vessali, who resigned from the College Station City Council to run for Congress, and George Hindman, a former NASA engineer and owner of a small business conducting aerospace research and development.

If no candidate passes 50 percent of the vote, the top two finishers head to a runoff in May.

Recently, Sessions has been caught up in the impeachment-related indictment of Lev Parnas and Igor Fruman, associates of Trump lawyer Rudy Giuliani, in their effort to oust ambassador Marie Yovanovitch. Sessions, who received at least $20,000 in contributions from them, denounced their “deception” and said he’s giving their contributions to charity.

Sessions’ rivals haven’t made an issue of his Giuliani connection, according to the Dallas Morning News.

TEXAS 28TH CONGRESSIONAL DISTRICT

Incumbent Democrat Rep. Henry Cuellar of Texas – dismissed on the left as “Trump's favorite Democrat” -- is facing a challenge from progressive Jessica Cisneros, who is trying to become the AOC of Texas.

Cuellar is a more conservative Democrat who has held an “A" rating from the National Rifle Association and has been targeted by abortion-rights groups.

Cisneros, a former intern in Cuellar’s office and lawyer, says Cuellar is out of touch with the Democratic district and called out Cuellar as “Trump’s favorite Democrat” in her campaign ad.

She’s been endorsed by Rep. Alexandria Ocasio-Cortez, Sen. Bernie Sanders, Sen. Elizabeth Warren and the Justice Democrats, which helped Ocasio-Cortez with her upset primary win in 2018.

Cuellar has pushed back efforts from the left to “purify” the party. His campaign has dismissed the Cisneros' endorsements from “celebrities” and said Cuellar’s history of consensus building is needed in the border district.

The Associated Press contributed to this report.