SAN FRANCISCO – Though the line of people snaking outside the Irish Cultural Center late Sunday morning kept growing, few “Beto 2020’’ shirts could be spotted in the crowd.

Democratic presidential candidate Beto O’Rourke was making his first appearance in famously liberal San Francisco since launching his campaign last month, but the folks coming out to hear him speak were not yet ready for a lovefest.

They needed to be convinced he was the best choice to take on President Donald Trump among the 20 or so contenders from O’Rourke’s own political party. Colorado Gov. John Hickenlooper stopped by the City by the Bay on Friday, and Washington Gov. Jay Inslee is scheduled to deliver a speech Thursday.

“There’s so many right now, I’m just trying to find out as much as I can about each one. My top 3 list changes every day,’’ said Christian Marquez, 35, a compliance officer for a startup who listed O’Rourke third behind Massachusetts Sen. Elizabeth Warren and Pete Buttigieg, the mayor of South Bend, Indiana.

An interactive guide:Who is running for president in 2020?

More:Donald Trump on 2020 Democrats: 'Rooting' for Pete Buttigieg, Beto O'Rourke is 'fading' and more

By the time O’Rourke was done delivering his 25-minute talk and answering questions for another 25 minutes, he may have moved up on Marquez’s rankings. Probably also sold a few more T-shirts.

The energetic former congressman from El Paso, Texas, revved up the crowd of several hundred with his positions on climate change, gender and racial inequality, health care, gun violence, reproductive rights and other topics close to liberals’ hearts.

The chants of “Beto! Beto!’’ that started resonating half an hour before his speech picked up considerable intensity after he was done.

“I don’t care to whom you pray or who you love, how many generations you’ve been in this country or whether you just got here this morning,’’ O’Rourke said. “All that matters to me is we’re Americans first. We have these challenges before us and we will overcome them.’’

O’Rourke, 46, is high on name recognition after his spirited – though ultimately unsuccessful – U.S. Senate run last year against Ted Cruz, but he’s lagging in the polls at this early stage of the race for the Democratic nomination.

A Washington Post-ABC News poll released Sunday shows him trailing former Vice President Joe Biden, Sens. Bernie Sanders, Warren and Kamala Harris, and Buttigieg. The survey also indicates the majority of likely Democratic voters, 54%, haven’t yet settled on a candidate.

That description applies to Cynthia Pelini and Jaime Pellicer, a married couple who lived for 23 years in his native Mexico and have spent the last 10 years in San Francisco. They’re desperate for a change from Trump’s policies, especially regarding immigration, and wanted to find out more about O’Rourke.

As bilingual speakers with bicultural sensibilities, they appreciate that O’Rourke – who sprinkled his address with several comments in Spanish – shares those traits.

Fast start:Biden quickly raises $6.3 million, marking the largest 24-hour haul from 2020 candidates

More:Beto O'Rourke releases 10 years of tax returns, reveals he and wife made $370K in 2017

“Especially with the problematic relationship right now between the two countries,’’ said Pellicer, who teaches international law.

Added Pelini, who grew up in New York: “He’s got to be much more in tune and much more sensitive and understanding of the border issues, immigration issues.’’

Indeed, as part of a California tour that began Saturday in Los Angeles, O’Rourke is highlighting the plight of immigrants who escaped poverty and violence in their native countries and are now facing a hardline stance from the Trump administration.

In December, O’Rourke led a delegation of lawmakers to Tornillo, Texas, to draw attention to the fast-growing number of undocumented minors at the detention facility in the small farming town less than 40 miles south of El Paso.

He has called the family-separation tactics employed by the current administration “inhumane’’ and “un-American,’’ and advocates citizenship for so-called Dreamers, people brought into the U.S. as children without proper documentation who have remained in the country.

Trump wants to do away with the program that protects them from deportation.

“This is our moment to decide how we will all be defined,’’ O’Rourke said Sunday. “Are we going to define ourselves by kids in cages? By withdrawing from the Paris climate agreement? By calling Nazis and Klansmen ‘very fine people?’’’

The crowd responded with a resounding, “No!’’

This part of the democratic process is what San Francisco resident Larry Olson had in mind when he convinced two of his three young children – daughter Brennan, 11, and son Trey, 6 – to join him on a venture to listen to O’Rourke.

Opinion:Why you should be skeptical of 2020 candidates: 'Astroturfing' can distort public opinion

Olson did have to dangle some incentives, like possible stops at the ice cream shop and the beach, for the kids to agree to come along to what for them figured to be a boring speech.

“But then I explained to them the process of politics and how this might be the person who becomes the president,’’ Olson said. “And we talked about El Paso and the border and the issues that are going on, so that piqued the little people’s interest.’’

Plus, Brennan had a question she wanted to pose to the candidate: “Why should it be you and not a female president?’’

She didn’t get to ask it, but over the next several months, that will be one of the topics O’Rourke has to address as he contends with a diverse field for the nomination.