Getting voters to the polls was the unspoken theme of...

DALLAS — In the first debate in the nation's hottest U.S. Senate race, neither candidate committed a major blunder or unleashed a rhetorical flourish catchy enough to become a viral rallying cry.

Instead, for most of 60 minutes, Republican Sen. Ted Cruz and Democrat Beto O'Rourke pressed buttons to ignite the most passionate elements of their bases.

For both candidates, the debate was not about changing minds. It was about boosting election day turnout among their most loyal followers.

With early voting just 29 days away and the first military and overseas ballots mailed out this weekend, the realities of campaigning in a state with historically abysmal midterm election turnout moved front and center. Both candidates tried to energize their most ardent supporters and get them to the polls on Nov. 6.

Cruz painted an image of Texas values being under assault from a socialist wave, with O'Rourke in the mold of Democratic socialist Bernie Sanders, billionaire socialist financier George Soros and former first lady Hillary Clinton.

The goal was to cast Beto O'Rourke as a threat to the Texas way of life, said Rice University political science professor Mark P. Jones.

WHAT THEY SAID: O'Rourke and Cruz take many shots in debate

O'Rourke calls for banning some types of guns, legalizing marijuana, preserving Obamacare and defending athletes who kneel during the national anthem. Polls show a majority of Texans disagree with him on those issues.

Cruz drove home the point when he told O'Rourke during one exchange that being there for Texans means fighting for them, and "not George Soros, not big liberal interests, but fighting for the values of Texas."

Later Cruz was asked to say something positive about O'Rourke. He responded in terms calculated to fire up his own base.

"Bernie Sanders believes in what he's fighting for, he believes in socialism," Cruz said from the stage at McFarlin Auditorium at Southern Methodist University. "Now I think what he's fighting for doesn't work, but I think you are absolutely sincere, like Bernie, that you believe in expanding government and higher taxes — and I commend you for fighting for what you believe in."

O'Rourke scored points by appealing to minority communities that must turn out on election day for the El Paso Democrat to have a shot at upsetting Cruz.

For most of the first half of the debate, O'Rourke decried inequalities in the justice system and the police shooting of an unarmed black man in Dallas. He also underlined his support for immigrants brought to this country illegally as children, the so-called Dreamers, and for African American football players who kneel during the national anthem.

"We've got to do something different than what we've been doing so far," O'Rourke, 45, said. "If African-Americans represent 13 percent of the population in this country and yet they represent one-third of those who are shot by law enforcement, we have something wrong."

Jones said for O'Rourke it was about presenting himself to black voters as a credible champion on those issues and enough of an ally that it's worth showing up in big — even historic — numbers to vote for him on election day.

Turnout in Texas mid-term elections has generally been among the worst in the nation. In 2014, just 4.6 million of Texas's then 14 million voters cast ballots in the midterm elections. That's just 34 percent of the state's registered voters and 25 percent of the voting age population in Texas. No midterm race has had more than 40 percent turnout since 1998.

O'Rourke was also tapping into his base's visceral reaction to Cruz, reminding them that Cruz, 47, led the government shutdown in 2013 and then spent more time as a presidential hopeful in 2016 campaigning in Iowa than representing Texans in Washington.

"Only one of us has been to each county in Texas and would have an idea about what Texas values are," O'Rourke said. "Within months of being sworn to service, your senator, Ted Cruz, was not in Texas. He was in Iowa. He visited every one of the 99 counties of Iowa."

Analysts expect even more fireworks in next debate

Many observers rated Cruz, a former presidential candidate, the more practiced and polished performer. That experience showed in Cruz's defense of his new-found alliance with President Donald Trump – once a bitter rival who insulted Cruz's family during the 2016 Republican presidential primaries.

"The transition of the Trump problem from a negative to a positive was the most impressive feat of the night," said Brandon Rottinghaus, a University of Houston political scientist. "Cruz made O'Rourke look trigger happy on impeachment and explained how he worked with Trump to make the economy better."

But Cruz also was forced to blunt O'Rourke's attacks on GOP health care proposals by conceding the need to cover preexisting conditions and pivoting to the problem of increasing premiums.

To Southern Methodist University political scientist Cal Jillson, the candidates won and lost different questions in different ways.

"The question both of them had trouble with, almost unexpectedly, was the guns issue," Jillson said. "Cruz wants to make the charge that O'Rourke would support judges and legislation that would remove people's guns. And O'Rourke wanted to make the argument that 'weapons of war' have no place in the street or in the classroom, and he described what an AR-15 does to a person who's hit."

Both made their points, Jillson said, but then both might have gone too far.

"Where Cruz kind of got off track was when he said that the removal of prayer from schools was one of the causes of gun violence," Jillson said. "That will resonate with some voters, but that's kind of a base-of-the-base argument on the Republican side."

Jillson saw Cruz recover against O'Rourke's snappy retort that "thoughts and prayers ... are not going to cut it."

"Cruz came back and said 'I pray for anyone who's in trouble,' which I thought was a broader kind of conservative rejoinder," Jillson said.

At bottom, Jillson saw the 90-second-answer debate format as a built-in advantage for Cruz, who he called the more "tactically wily" of the two.

"They're very different people, with Cruz being very aggressive and often ending his answers with a sort of bumper sticker accusation or charge, in an attempt to get O'Rourke off message," Jillson said. "He's had a lot of practice at that 90-second answer, and that's something you've got to learn. It's not something you do naturally, particularly for O'Rourke, because he's a long-form orator. It's JFK. It's MLK. There's cadence to it, but it goes on for paragraphs."

Either way, the two candidates' contrasting appeals to Texas values came through loud and clear. The opposing messages also were leavened through Cruz's attacks and O'Rourke's efforts to remain upbeat.

"When Cruz talks about Texas values, he sort of imagines himself on the ramparts of the Alamo," Jillson said. "You know, the Mexicans are coming. It's freedom. It's liberty. It's me against tyranny. Whereas O'Rourke was much broader. It was about families, parents taking care of children and schools that work, that kind of stuff. That sort of narrow, traditional view of Texas values, while true enough, in a debate setting, doesn't quite resonate the way talking about someone's kids does."

The final measure of that contrast emerged with the moderators' appeals to each candidate to find something nice to say about the other.

"It's a light into their respective souls and strategies," Jillson said. "O'Rourke, given the opportunity to say something nice about Cruz, said something nice about Cruz. And Cruz, given the opportunity, couldn't bring himself to do it. So he said 'me too' about valuing public service, but then wanted to place the shiv one last time."

If nothing else, the debate reinforced popular perceptions of the two candidates.

"Cruz the knife fighter is well-known, and respected if not liked by conservative Texans," Jillson said. "With Cruz, they say, 'I might not want to have a beer with that guy, but if it's a knife fight in the alley, I know he's not going to be disarmed.'

"Whereas people who respond to O'Rourke respond precisely to his ability to sort of rise above the political violence and partisanship."

At bottom, O'Rourke appears to have emerged from the debate as a "blue" challenger in a "red" state who has run a surprisingly strong campaign and performed credibly in a head-to-head contest – always the threshold requirement for a challenger who is running behind in most polls.

In light of a testy Round One, speculation has already begun on what adjustments the candidates will make in the next debate, especially if the polls remain close.

"Round two will be more violent from both sides who seek high stakes," Rottinghaus said, "so we're likely to see more fireworks."

jeremy.wallace@chron.com