So what's O'Rourke's game plan to become the first Democrat to win a Texas Senate seat in almost 30 years? He's going to convince voters who feel ignored, isolated and even targeted by Trump and the Republican Party's policies that there is strength in numbers.
"You tell them we're not a red state," O'Rourke said to a packed house of supporters and local business representatives Friday during a town hall at the Texas Theatre. "We're going to give everyone a reason to vote."
O'Rourke, who serves Texas' 16th congressional district, plans to challenge the incumbent Cruz in the November election and may get his wish if his numbers stay as strong as a recent University of Texas/Texas Tribune poll says they are at
Texas State Rep. Rafael Anchia introduced O'Rourke with a chilling characterization of how the national political dialogue has shifted to targeting communities instead of including them.
"I feel like the communities I represent are under attack, whether they are LGBT, Latino, Muslim or, as we've seen with the rise of anti-Semitism, against our Jewish communities," Anchia said. "Our democracy is under attack."
Anchia said O'Rourke will bring a sense of leadership back to Texas' junior Senate seat and will stand up to those who threaten America's democracy.
"We need leaders who don't sit in the back and put party over country," he said. "We certainly don't need a senator who's afraid of Trump or [Russian President] Vladimir Putin."
Anchia said he's known O'Rourke since his time on the El Paso City Council and "more than anything, he is courageous."
"He not only joined the race when others wouldn't," Anchia said. "He is not afraid to stand up to the president or other foreign powers, and that's most important."
He rebuked the notion that these shootings are just a natural presence of evil America needs to accept and cannot change.
"How can we be a country that can't acknowledge you don't need a gun like an AR-15?" O'Rourke asked. "When we lose 15,000-plus of our fellow Americans at the hands of guns or those who take their own life with a gun ... we have to stop responding to these things as though they are a natural disaster. [Hurricane] Harvey was a natural disaster. People coming into schools and slaughtering children is not a natural disaster."
O'Rourke vowed to the crowd to keep his campaign on the grassroots level, especially when it comes to his contributions compared with Cruz, whom he called "the poster child for taking money from the [National Rifle Association]."
"I don't know what my score is with the NRA," he said. "I've never received a dime from them. I promised I'm only going to work with the people in this campaign, not with PACs, not with special interests."
O'Rourke also talked about health care access and how Texas has the highest number of uninsured citizens in the country.
"We're going to pave the way on universal health care," he said.
O'Rourke also fielded questions from the crowd about making college more affordable.
"What are we doing making it harder to pursue an education, especially when the benefit spreads to all of you?" O'Rourke asked. "I've already anticipated the attacks. 'God, it will cost billions.' You're right, but it's going to pay hundreds of billions in dividends. ... I think this is an investment that's well worth making."
O'Rourke also wants Texas to lead the country on immigration issues using personal stories of Texans who have contributed to America. He said Texas can discuss ideas other than building a wall or deporting immigrants.
"How can we not lead the way on immigration?" he asked. "No one else will be able to do it like we do it in Texas."
The attendees seemed receptive of O'Rourke's message, but some hadn't made up their minds about the primary or the election.
"I still need to do a little bit more research, but I'm leaning towards him," said Stephanie Sunseri of Dallas. "I liked what he had to say."
Huyen Nguyen of Dallas said she appreciated O'Rourke's views on immigration but would like to know more about his plans to protect immigrants already in America.
"I definitely feel like I agree with him on how we should help out those that have no other home other than America," Nguyen said. "It's un-American to kick [out] someone who has been here more than 90 percent of their lives, and I'd like for him to have touched a little bit more on what can we do immigration-wise to get them in a better, more efficient process to become citizens. I'd like to hear more from him on that if he were to become the senator."
Ivan Lopez, a sophomore at Eastfield College, attended the town hall as part of a history class project and to help gauge his support of the candidate in the general election. He said O'Rourke "won me over for sure."
"We think the same way in some places," Lopez said. "I know he's pro-choice and I'm pro-life. He's big on immigration, and I come from immigrant parents, so that touches at home, and I feel strong for what he stands for in that situation."
Alicia Lanier, a neighborhood precinct chairwoman from north Irving who voted for O'Rourke in the primary, said she likes his left-of-center stances on issues like universal health care,
"He's very progressive," Lanier said, "so he shares a lot of my views."
She also said she feels O'Rourke still has a way to go to compete with a seasoned politician like Cruz.
"[Cruz] was very outspoken, but then he just started to tow the Trump line," Lanier said. "I would love to see Beto put up a good fight. The only thing he needs more of is name recognition and [to] get in front of more people."
Lopez said O'Rourke has a shot.
"At this point, I feel like it can go either way," he said. "I feel like the presidential election damaged Ted Cruz somewhat. After everything Trump did to him, I wouldn't even have been on the phone line and said, 'Hey, vote for Trump.'"
O'Rourke said he can win if the turnout remains as strong as Friday's town hall meeting.
"There are too many of us to fail," O'Rourke said. "We are going to win this election."