Beto O’Rourke had, it seemed, already made up his mind he was going to run for Ted Cruz’s U.S. Senate seat next year.

But among the many hurdles the three-term Democratic congressman from El Paso would face, semiobscurity seemed hard to crack. He was little known outside of his hometown — no El Paso native has ever won statewide office — despite recent trips to virtually every corner of the state to raise his profile.

That changed Tuesday, when O’Rourke and his colleague, Will Hurd, a second-term Republican from Helotes, found themselves unable to fly from San Antonio into snowbound Washington in time for some House votes Wednesday. Instead, at O’Rourke’s instigation, they rented a Chevy Impala and hit the road for the nation’s capital.

Thus was born a 30-hour bipartisan road trip (plus four hours sleeping at a Nashville, Tenn., hotel), much of it streamed on Periscope and Facebook Live, that O’Rourke from the outset described as the "longest cross-country livestream town hall in the history of the world," and which over the course of their 1,600-mile journey garnered encouragement from politicians of both parties, 2.6 million views online and the kind of avalanche of positive media coverage that most politicians will never see in a lifetime.

O’Rourke had all but announced his Senate candidacy last Saturday before a rapt audience in a San Antonio burger joint’s beer garden festooned with "Run Beto Run" signs.

FIRST READING: Beto O’Rourke will run for the Senate, because with Trump and all, `How could you not.’

"Two thousand eighteen, if you want it to, begins tonight, right here with you and me and everyone who is willing to work their hearts out to make the change that we know is necessary and that we know for the first time in a generation is possible in this state," said O’Rourke, gesturing expressively in the soft light of dusk.

As O’Rourke spoke, a similar event was getting underway in a sports bar back in his hometown, where Joaquín Castro, the third-term Democratic congressman from San Antonio, would tell another adoring audience, "We need a senator that works for Texas. Ted Cruz works for Ted Cruz."

Castro promised a decision on whether he would enter the race by the end of April, roughly the same timetable O’Rourke has set for his own decision.

But Castro, like his twin brother, Julián, the former mayor of San Antonio and secretary of housing and urban development in the Obama administration, carries a far heavier burden of expectations than the lesser known and more politically footloose O’Rourke. And Joaquín Castro, 42, would be risking a far more promising career in the House of Representatives than O’Rourke, 44, who has pledged to serve no more than four terms and has openly defied Nancy Pelosi, the House minority leader.

So, come the end of April, it would be astonishing if O’Rourke didn’t declare his candidacy for the Democratic nomination for the U.S. Senate, and surprising if Castro did.

"I think O’Rourke has decided he is going to do this, " Southern Methodist University political scientist Cal Jillson said, "whereas I think both of the Castro brothers are much more careful and calculating."

But O’Rourke would have to build a statewide campaign from scratch. And he would be facing the most recognizable name in Texas politics in Cruz, not to mention the long odds that come with any Democrat seeking to win statewide in Texas.

The bipartisan road trip

O’Rourke has shown a gift for nimble political timing, insinuating himself into the state and national consciousness on the spur of the moment, at just the right time and in a way that defined him not as a polarizing partisan, but as the exact opposite.

The road trip almost instantly took on the endearing quality of a classic buddy movie, albeit with a lot more conversations on national policy — from opioid addiction to the federal budget freeze — than the genre usually allows.

O’Rourke and Hurd, whose vast district stretches from San Antonio to the outskirts of El Paso, talked about areas of agreement.

"We both agree a border wall from sea to shining sea is the most expensive and least effective way to do border security," Hurd said.

They talked about areas of disagreement, both substantive and less so.

O’Rourke: "I like cake. My mom’s a great baker."

Hurd: "I like cake, but pie is so much more versatile."

They talked about music.

"First concert," said Hurd, throwing out a topic.

O’Rourke: "Quiet Riot. ‘Come on Feel the Noize.’ El Paso County Coliseum."

Hurd: "Hootie and the Blowfish. Austin, Texas."

FIRST READING: Notes from Beto and Will’s livestreamed, bipartisan, Texas-to-D.C. town hall road trip

They received calls from current and former members of Congress, from Democrats Joe Kennedy of Massachusetts and Tulsi Gabbard of Hawaii to House Republican Majority Leader Kevin McCarthy of California and former House Speaker Newt Gingrich.

U.S. Sen. John Cornyn of Texas, old enough to be their father, called to make sure there was no distracted driving going on.

They played AC/DC’s "Highway to Hell" to satisfy a request from House Speaker Paul Ryan.

It caught on, their live video feed amplified by Facebook co-founder and CEO Mark Zuckerberg, who posted it for two hours on his Facebook page. News of the road trip was splashed across the front pages of newspapers in El Paso, San Antonio and Dallas, featured in The New York Times and The Washington Post, on "Good Morning America" and the CBS Evening News, on NPR, and on virtually every other outlet with the least interest in politics or male bonding.

As BBC correspondent Laura Bicker reported, "They drove through the night, capturing the attention of a divided nation."

They arrived at the Capitol on Wednesday evening with a half-hour to spare. The next morning, the pair appeared on "Fox & Friends" and MSNBC’s "Morning Joe," where the beaming host, Mika Brzezinski, declared them "adorable."

‘A great problem to have’

Texas Democrats last won statewide office 1994. Cruz was elected to the Senate by a margin of 16 percentage points after a come-from-behind victory over Lt. Gov. David Dewhurst in a GOP primary runoff. Cruz quickly became the most popular Republican in Texas, but his strong but failed presidential bid and his up-and-down relationship with candidate and now-President Donald Trump have brought his approval ratings down to earth.

Meanwhile, this is about the time in the political cycle when Democrats succumb to hope over experience.

In June 2013, Democratic hearts soared when then-state Sen. Wendy Davis of Fort Worth filibustered abortion legislation, drawing national attention and social media acclaim that led her to a run for governor in which she raised an enormous amount of money on the way to a 20-point drubbing.

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"They’re fooling themselves again, which they happen to do every two or four years in this state," said Matthew Dowd, the ABC News political analyst who as a political consultant helped elect and re-elect Democratic Lt. Gov. Bob Bullock, and was chief strategist for President George W. Bush’s campaign in 2004 and for Arnold Schwarzenegger’s successful outsider bid for California governor in 2006.

This time, Dowd said, Democrats are convinced that "people don’t like Trump in Texas, therefore Democrats are going to win."

Dowd, who lives in Austin, believes there is a potential path for victory in the Cruz race for a centrist independent — and he is contemplating becoming that candidate.

But, he said, "in my view, if it’s Beto O’Rourke against Cruz, Cruz wins and probably wins by double digits. If it’s Joaquín Castro vs. Ted Cruz, it’s basically the same thing, and instead of losing by 14 points, he might lose by 10 points.

"I mean, Texas is still a right-of-center state, broadly," Dowd said. "If (voters) get a choice between a very left-of-center Democrat and Ted, they’re going to pick Ted."

Trump won Texas by just 9 percentage points, though, giving Democrats hopes that the state’s political pendulum is slowly beginning to swing.

Still, if history holds, Democratic turnout will be lighter for the 2018 midterm election. In 2014, the party’s statewide candidates all lost by 20 points or more.

But Trump’s epic unpredictability adds an element of uncertainty for 2018 in Texas as everywhere else and, for Democrats, an urgency to harness all the anti-Trump energy at the grass roots.

"Talk to anybody who works in politics in Democratic and progressive circles in Texas," said Jeff Rotkoff, a veteran Democratic political strategist who is now director of campaigns for the Texas AFL-CIO. "You would get near unanimous agreement with the statement that interest in political participation by average folks who have not participated in politics in the past is through the roof, and it’s impossible not to connect that to Trump."

The state Democratic Party says it finds itself deluged with unusual interest by potential candidates at every level, and Texas Democratic Party Chairman Gilberto Hinojosa said that even the possibility of an O’Rourke-Castro contest does not distress him.

"Truthfully, after so many years having a difficult time getting strong candidates to run for the U.S. Senate, it’s a great problem to have," Hinojosa said.

"I think it’s a healthy thing that both of them feel that they would seriously consider seeking the nomination for the U.S. Senate because they think that Ted Cruz is beatable and because they believe that the atmosphere that is being created in Texas and all across America by the Trump phenomenon is going to make a better atmosphere for Democrats in 2018," Hinojosa said. "Trump is the gift that keeps on giving."

O’Rourke said he has been buoyed by recent visits to Fort Worth, Wichita Falls, Amarillo, Austin, Killeen, Waco, College Station, Corpus Christi, Brownsville, McAllen, Laredo, Houston, Dallas and any number of smaller town in between, often meeting with veterans’ service organizations. O’Rourke serves on the Veterans Affairs and Armed Services committees.

Midland, Odessa, Big Spring and Abilene were on the schedule for this weekend.

Castro has drawn big crowds without really trying.

More than 300 people filled the courtyard at the Scoot Inn in East Austin for a rally Feb. 11.

Three weeks later, Greater Houston Democrats invited Castro to come to Axelrad Beer Garden, and 600 people showed, many of them new faces to Democratic Party politics.

Nothing to lose

Castro has a lot more to lose than O’Rourke.

He is in good with his party’s leadership, with a seat on the Foreign Affairs and Intelligence committees, where he could play a high-profile role in the investigation of the Trump administration’s Russia ties.

For years, both he and his brother have been marked as men of destiny, the Texas Democrats most likely to break through as statewide candidates when the time is right.

Julián Castro, who was seen as a potential running mate for Hillary Clinton last year, has taken himself out of consideration for elective office in 2018 to write a book.

Of Joaquín Castro, Mary Beth Rogers, who ran the 1990 campaign of Ann Richards, the last successful Democratic candidate for governor, said, "He has real sense of Texas, and I’m impressed."

"I think he sees reality, and that may hold him back," said Rogers, who last year wrote a book, "Turning Texas Blue: What It Will Take to Break the GOP Grip on America’s Reddest State." But, she says, "he also possesses a firm understanding of what it will take to break through."

On the other hand, come what may, O’Rourke is not long for the House.

As he told the folks at Tycoon Flats, the burger restaurant in San Antonio, last weekend, "I am one of the few members of Congress, and maybe the only Democrat, who is not just for term limits, who has not just filed term limits legislation, but has promised to adhere to term limits myself."

In the same spirit, he voted for Tim Ryan, a 43-year-old congressman from Ohio, who challenged Pelosi for speaker, and was vocal about it.

Early in last week’s road trip, O’Rourke said, "Our party leadership is probably not super excited that we’re doing this. But screw that line of thinking."

Castro and O’Rourke have nothing but warm praise for each other.

In El Paso, Castro spoke about his grandmother, who came to San Antonio as an orphan escaping the violence of the Mexican Revolution. His parents were active in the Mexican-American civil rights movement.

He and his brother graduated from Stanford University and Harvard Law School.

O’Rourke, who as a child took the Spanish nickname for his given name Robert, is the son of a former El Paso county judge.

He graduated from Woodberry Forest School, a prep school in Virginia. In the early 1990s, he toured the country as part of the El Paso punk band Foss. He received a bachelor’s degree in English literature from Columbia University. After college, he started a successful web design firm, won election to the El Paso City Council and then defeated a 16-year Hispanic Democratic incumbent for Congress. Unlike Castro, O’Rourke is fluent in Spanish.

According to the Center for Responsive Politics, as of 2014, the last year for which figures are available, O’Rourke ranked 43rd in the House with an estimated net worth of $9.5 million. Castro ranked 426th among the 435 members of the House with an estimated net worth of $61,500.

But O’Rourke has never sunk his personal wealth into a campaign, and he talks a lot about taking the money out of politics.

"I am also one of three in Congress out of 535 who doesn’t take political action committee, PAC money, special interest contributions," he told his audience in San Antonio.

"The possibility of him running for Senate just makes me feel giddy," said Catherine Hedrick-Moser, a young mother who had recently moved from El Paso to San Antonio and came to see O’Rourke at Tycoon Flats.

"I love the Castros — be real clear: I love the Castros, and I would love to support Joaquín, but he’s going to have to get out there very quickly or he’s going to lose his support here in San Antonio," said Terry Brechtel, a former San Antonio city manager who worked with the twins’ mother at City Hall.

"Castro has a more national name recognition," said Julie Nitsch, an organizer for the Bernie Sanders campaign in Austin who won election to the Austin Community College Board of Trustees last year. But Nitsch, who was not at the San Antonio event, said O’Rourke might better capture the moment, and the need for Democrats to reach beyond their usual base.

"The climate right now is, we don’t want next-in-line," Nitsch said. "It’s who else do you have?"

And, Nitsch said, as O’Rourke proved last week, "He has a talent and a knack for connecting with people."

As Hurd said, deep into their drive, "Once you get something in (Beto’s) mind, he’s not going to stop until he gets there."