AUSTIN — State Rep. Beto O’Rourke, a Texas Democrat, made a splash when he drove cross-country with a Republican congressman, but with a bid for the U.S. Senate, O’Rourke is trying to make history. 

To do so, the third-term El Paso native may well have to win a 2018 primary against one of Texas’ hottest political stars, U.S. Rep. Joaquin Castro of San Antonio, before tackling Republican incumbent Sen. Ted Cruz in what’s still a bright-red state.

“He definitely has an edge by getting in the race early,” Brandon Rottinghaus, a University of Houston political science professor, said of O’Rourke. “He’ll be able to capitalize on some momentum from that.”

And, Rottinghaus said, the March road trip from Texas with state Rep. Will Hurd, R-Helotes, which the pair embarked on after storms shut down East Coast airports, was a masterstroke that felt like an “organic” example of two lawmakers solving problems on their own like “a normal person would do.”

Now O’Rourke’s challenge is to convert the buzz into campaign bucks and backing.

“Texas Democrats’ donations have been an ATM for the national Democratic party for some time,” said Manny Garcia, the Texas Democratic Party’s deputy executive director. “In Beto’s story, we’re seeing a lot of low-dollar grassroots donors.”

O’Rourke is one of a handful of House of Representatives members who didn’t take PAC contribution in the 2016 election. 

He and Rep. Ro Khanna, D-California, last month introduced the No PAC Act, which would prohibit members of Congress and those running for the U.S. House or Senate from taking money from political action committee, other than that of the candidate’s. 

“We need to get special interest money out of politics,” O’Rourke said in a statement. “This bill is an important step to do just that.”

But that’s not necessarily a plus.

“The fact that he’s not willing to take PAC money is seen as being a self-imposed limitation,” Rottinghaus said. “There’s a sense that not fully investing in all the resources would be seen as a real detriment.”

Should Castro enter the primary contest, the state Democratic party will stay on the sidelines until there’s a winner.

Garcia said that having two charismatic contenders is “an incredibly good problem to have,” and “shows how far we have come.”

Rottinghaus, however, gives Castro the edge, should there be a Texas Democratic primary showdown for the seat Cruz occupies. 

“There’s the sense that he’s the heir apparent to a statewide win,” Rottinghaus said. “Castro’s got much better name recognition.”

And, Castro is Latino, which gives him an edge with Latino voters, Rottinghaus said. 

Although Donald Trump’s ongoing effort to build a wall is unlikely to win widespread approval among Latinos, Cruz has regained some footing after his unsuccessful presidential bid. 

Among 1,200 Texas voters surveyed in February 2017 by the University of Texas at Austin’s Texas Politics Project, Cruz’s “approve strongly” and “approve somewhat” job-approval numbers totaled 38 percent.

That was up from a 32 percent favorability showing in October 2016, after Cruz came under fire when he failed to endorse Trump in a GOP national convention speech.

Garcia points to Democrats’ growing strength in Texas cities as sign that the race for the Senate seat could go his party’s way in the midterm election.

Rottinghaus likened a Democratic Cruz challenger to the defenders  who stepped up to cross a line in the dirt at the Alamo: undaunted but doomed. 

Still, he said, “everybody’s unbeatable, until they get beat.”

John Austin covers the Texas Statehouse for CNHI’s newspapers and websites. Reach him at jaustin@cnhi.com