As Beto O'Rourke relaunched his 2020 presidential campaign in his hometown of El Paso Thursday, the former Texas congressman directly addressed the growing number of calls for him to return home in the wake of a deadly mass shooting.

"There is a big part of me that wants to stay here. I love El Paso. There have even been some that say I should stay in Texas and run for Senate," he said. "But that would not be good enough for this community, for El Paso and for this country. We must take the fight directly to the source of this problem – to the person that has caused this pain and peril: Donald Trump."

In an emotional speech Thursday morning, O'Rourke reaffirmed his commitment to the 2020 presidential race – and unseating President Donald Trump – arguing that his leadership is necessary for a country still reeling from several recent mass shootings and rampant gun violence. He returns to the campaign trail 12 days after a gunman opened fire at a Walmart in El Paso, killing 22 people and injuring dozens.

Photos: A Deadly Day of Mass Shootings View All 24 Images

O'Rourke, who garnered massive attention in his close race against Sen. Ted Cruz of Texas in 2018, has struggled to gain the same kind of traction in a race with more than 20 Democratic candidates. He's consistently gotten single-digit support in polls and hasn't raised the same kind of funds like he did for his Senate bid.

That has led to calls for him to drop out and pursue another Senate run, most notably from an op-ed in The Houston Chronicle asking for him to "come home." Democrats have a tough path to reclaiming the Senate, but some argue they'd have a better chance if longshot presidential candidates instead opted to run for the Senate. And many Democrats acknowledge that if they win the White House, they'll also need to hold the House and take back the Senate to pass their top priorities, like new gun legislation.

But O'Rourke is hoping to put an end to those calls and jumpstart his 2020 bid six months before the first votes are cast for the Democratic nomination. And he plans to do that by charting a less traditional path and directly challenging Trump.

The former congressman dedicated much of his speech to recounting stories about meeting with victims in the aftermath of the shooting and the resolve of a community still in mourning and roiled by fear. A small group of invited guests attended the relaunch where O'Rourke spoke against the backdrop of El Paso and Ciudad Juárez, Mexico, which is just over the border.

O'Rourke took aim at a Congress that is "too craven" to enact new gun laws and a pervasive racism "that is as old as America itself." The suspected shooter told authorities he was targeting Mexicans and minutes before the shooting, he posted an online manifesto echoing language used by Trump and calling the shooting "a response to the hispanic invasion of Texas." O'Rourke argued Trump lacks the leadership needed to heal the country, end racism and prevent future mass shootings.

"It's almost as if the bigger the lie, the more obvious the injustice, the more furious the pace of this bizarre behavior, the more incapable we are in seeing it and naming it," O'Rourke said. "This attack on El Paso is an attack on America. It's an attack on our ideal of what America can be, an America that has not yet been for so many."

"If we do not wake up to this threat, then we, as a country, will die in our sleep."

In the wake of the El Paso shooting and another one less than 24 hours later in Dayton, Ohio, Congress and the White House have been scrambling to address the deadly incidents and see if there's any common ground between the parties on passing new gun safety measures.

House Democrats, whom earlier this year passed a universal background checks bill, have been pressuring Senate Republicans to allow consideration for the measure on the Senate floor. Trump has been calling for stronger background checks and "red flag" laws that would temporarily seize firearms from those who pose a threat to themselves or others. But there is skepticism about whether he'd follow through on background checks.

O'Rourke plans to make gun control a central issue in his campaign going forward. He lamented that there are too many guns and wants to implement a mandatory buyback program for assault weapons. The accused El Paso shooter told authorities he used an AK-47 assault rifle.

The president has already poured cold water on considering an assault weapons ban, arguing that there's not a "political appetite" for that. The federal assault weapons ban implemented by Congress in 1994 expired a decade later.

Now that he's back actively campaigning, O'Rourke said he won't be immediately going to traditional caucus and primary states like Iowa and New Hampshire, respectively. He said he'll be traveling next to Mississippi where U.S. Immigration and Customs Enforcement raided food processing plants and detained hundreds of supected undocumented immigrants.

Meanwhile, Trump allies criticized O'Rourke's speech, accusing him of using the "tragedy in his hometown to bolster his struggling presidential bid."