What to Know Beto O'Rourke told Oprah Winfrey in an interview Tuesday that he would decide this month whether or not he would run for president.

A Democratic presidential candidate has not won Texas since 1976, and no Texas Democrat has won statewide office since 1994.

O'Rourke lost to Sen. Ted Cruz (R-TX) in the 2018 midterms by less than three percentage points.

Former U.S. Rep. Beto O'Rourke told Oprah Winfrey Tuesday that he would decide by the end of the month whether he is going to run for the 2020 Democratic presidential nomination. O'Rourke suggested he's leaning toward entering race, hoping to build on the momentum he gained during his 2018 U.S. Senate campaign against Republican Ted Cruz.

The state of Texas hasn't voted for a Democrat in a presidential election since the state's electoral votes went to Jimmy Carter in 1976. In fact, the Lone Star State hasn't even elected a Democrat to a statewide office since Bob Bullock was reelected lieutenant governor in 1994, along with a handful of other statewide — but not national — wins.

There are several other factors working against O'Rourke. An incumbent president has failed to win reelection just twice since World War II: Carter in 1980 and George H.W. Bush in 1992.

But Democrats have dreamed of turning Texas blue for decades, and O'Rourke showed in 2018 that it might be on the cusp of turning purple, though the party still did not win a statewide post in the midterm elections.

While it wouldn't be impossible for O'Rourke to win Texas as the Democratic nominee, it would likely take a perfect storm for him to do so.

"A presidential run, where more people are engaged, more people are excited about the process, that will only push Texas even more to the brink of being a battleground state," The Dallas Morning News political writer Gromer Jeffers Jr. said. "Now, that means Republicans will come out too."

But the most influential aspect of the 2020 general election campaign might be something the eventual Democratic nominee can't control.

The Trump Effect

"The main thing (O'Rourke) can't control is Trump and what Trump does and how the country experiences what he does over the next year," SMU political science professor Cal Jillson said. "Because the second year (2020) is the campaign."

An October 2018 University of Texas/Texas Tribune poll found that a combined 48 percent of Texans either "approved strongly" or "approved somewhat" of Trump, while a combined 45 percent either "disapproved strongly" or "disapproved somewhat."

Those numbers indicate Trump has solidified support among Republicans since he was elected president. In an October 2016 University of Texas/Texas Tribune poll, just 31 percent of respondents had a "very favorable" or "somewhat favorable" view of then-candidate Trump, while a combined 58 percent had a "somewhat unfavorable" or "very unfavorable" opinion.

"Trump remains popular with moderate Republicans and independents," Jeffers said. "He is strong with the base and, being a sitting president, he's going to have probably a little more strength than he did as Trump the candidate."

Nationally, Trump steadily holds an approval rating between 38 and 42 percent, Jillson said. But in Texas, that number is consistently eight to 10 percentage points higher.

"If you're with Trump after the last two years, you're with him in a determined sort of way," he added. "And if you're off him, you're off him in a very determined way and looking for an alternative. I think those numbers do reflect ongoing polarization."

A Full-Time Candidate

After losing to Ted Cruz in the 2018 U.S. Senate race, O'Rourke no longer holds elected office. It could be a strength and a weakness.

In 2016, neither major party's presidential candidate held public office and, in 2012, Mitt Romney was not in office when he won the Republican party's nomination.

However, before Trump, no one has won the presidency without being in office since Ronald Reagan did so in 1980, after he served as California's governor from 1967-75. He did not seek a third term because he ran for the Republican presidential nomination in 1976, but lost to Gerald Ford.

Is that a place where similarities between O'Rourke and Reagan could begin and end?

"It will be an ongoing fight to remain in the public eye when he's one of 15, 20, 25 Democrats running for the nomination," Jillson said. "But on the other hand, it means that he can run for president full time. He's got nothing else demanding his time and attention, and that has been something that has worked well."

Jillson added that not holding office would give O'Rourke extra time to campaign, put a team together and fundraise. One of the former congressman's strengths in the 2018 Senate race was the time he spent traveling around Texas, something he could devote even more time to nationally if he's not in office.

"O'Rourke will still be in the minds of the public, in the minds of Texans – not just Texans, but the entire country," Jeffers said. "The enthusiasm will probably still be there for him and just like with any candidate, he's going to have to try to keep it going, especially in a big field."

Texas' Largest Counties

If a candidate O'Rourke were to win the nomination, one of the places he'd have to find growth to turn Texas into a battleground state would be in its largest counties.

Democratic presidential nominee Hillary Clinton received a combined 53.9 percent of the vote in the 10 largest counties in 2016, while O'Rourke upped it to 59.2 percent in 2018.

"If Trump continues to be erratic and continues to worry suburban white women, who normally vote Republican — and increasingly their husbands — then yes, you could get a continuing erosion of the Republican grip on suburban districts, which they have had for a half-century or more in Texas," Jillson said.

Of North Texas' four largest counties, three — Collin, Denton and Tarrant — have voted reliably Republican for decades. However, O'Rourke narrowly won Tarrant County against Cruz in 2018 and received 46.5 percent of the vote in Collin County.

Jeffers said he thought an erratic president could make O'Rourke more palatable to Collin County voters.

"You have a lot transplants moving into Collin County," he said. "The Toyota plant over there, people from California plus the East Coast are moving into Collin County and counties like that. They're more prone to look to a candidate like O'Rourke, whereas people in Denton County — although Denton County is growing too — still contains some of the state's most conservative voters and they're likely to support Trump, just as they have supported other Republicans."

O'Rourke earned 45.5 percent of the vote in Denton County in 2018 and still had an eight-point gap to reach Cruz.

Most of the state's largest counties have turned reliably blue. The two largest counties, Harris and Dallas, have voted for the Democratic nominee in each presidential election since 2008. Bexar County has voted for the Democrat in five of the last seven, and Travis County, the fifth-largest in the state, has voted for the Democratic nominee for president in each election since 1992, with the exception of 2000.

Tarrant County is the only one of the five largest that has not voted for a Democrat for president dating to 1992, but O'Rourke won the county in his Senate race against Cruz by 0.7 percentage points.

Working in O'Rourke's favor is that he is a Texan and Clinton was not.

Republican George W. Bush garnered landslide victories in Texas in 2000 and 2004, winning by nearly 22 points in his first run for office and almost 23 points four years later. In fact, in 2000, Bush even turned Travis County, where Austin is located, red — the only time the county has voted for a Republican for president since 1992.

Julian Castro

There is another Texan running for the Democratic nomination. Former San Antonio mayor and House and Urban Development Secretary Julian Castro launched his campaign Jan. 12.

However, Jillson and Jeffers agreed, by playing it safe in the years leading up to 2019, Castro, while still popular, may have missed his opportunity.

"I think Democrats in Texas are still very favorably disposed to Julian Castro. But O'Rourke took the state by storm very unexpectedly in 2018 and he was just a shooting star that eclipsed Castro, partly because O'Rourke did it and Castro whiffed," Jillson said. "Castro didn't think it was possible and so he didn't make the run O'Rourke did and almost beat Cruz."

"It'll be hard for Castro to get traction, not just in the early primary states, but in his home state of Texas," Jeffers said. "Because what Beto has done, is become the most popular Democrat in the state now. There's just no other way to put it."

In a Jan. 30 Politico/Morning Consult poll of potential 2020 Democratic candidates, Castro received just one percent of the vote. O'Rourke received six percent, while former vice president Joe Biden held a substantial lead with 33 percent.

There are a lot of "what-ifs" involved in O'Rourke's run for president. First of all, he'd have to survive the early primary states like Iowa, New Hampshire and South Carolina and stay relevant until Texans vote. He could be helped by Texas moving up its primary to Super Tuesday — March 3, 2020 — something California has done as well, which could help a candidate like Sen. Kamala Harris, D-Calif.

O'Rourke, still, has not received the same level of interest as the top two people named in the Jan. 30 poll: Biden and Bernie Sanders. O'Rourke sits in a tie for third with Sen. Elizabeth Warren, D-Mass.

But if everything were to come together perfectly, it's conceivable that the former congressman from El Paso could capture lightning in a bottle twice.

"It's very difficult to have a dramatic run like he had in 2018 and then reprise that two years later, because people have already looked at you, they've already gotten excited about you," Jillson said. "That excitement wasn't rewarded, and to sort of reproduce it completely is very difficult to do, but certainly not impossible."