Updated Thursday at 9:10 a.m. with details from O'Rourke's address in El Paso, and the Trump campaign's response.

WASHINGTON - Beto O’Rourke resumed his campaign on Thursday, ending a 12-day hiatus that began when 22 people were gunned down in a bustling Walmart in his hometown of El Paso.

In a speech from El Paso, he reframed his bid for president as a crusade against gun violence and intolerance and most especially President Donald Trump. He'll underscore the new approach with a visit on Friday to Jackson, Miss., to meet with immigrants fearful after last week's raids on meat processing plants in the area.

"That attack on El Paso is an attack on America. It is an attack on our ideal of what America can be," he declared, asserting later that Trump is the "person who has caused this pain."

So, he said, "to those places where Donald Trump has been terrorizing and terrifying and demeaning our fellow Americans, that's where you will find me in this campaign."

The attack drew the incumbent's attention. Trump campaign spokesperson Samantha Cotten accused him even before the half-hour speech had ended of "using the tragedy in his hometown to bolster his struggling presidential bid. ...Texans know O'Rourke is more interested in his own personal political gain than he is in helping his hometown heal."

O'Rourke's campaign announced the plan on Wednesday morning, taking pains to quash speculation that he might use the speech to drop out of the race. He reiterated that on Thursday.

O'Rourke noted that the killer's mother was alarmed enough at his purchase of the AK-47 he would later use for mass murder that she called police, only to be told he'd bought it legally and there was nothing they could do.

"We have a racism in America that is as old as America itself," he said, and American leaders have always tried to confront that racism, "til now." Instead, he said, Trump calls immigrants "animals, and predators and killers" and warns of an invasion -- a warning the shooter in El Paso took to heart.

"What he says and what he does does not just offend our sensibilities as a country. It changes who we are as a country," O'Rourke said, laying blame for the El Paso rampage and spikes in hate crime at Trump's feet. "You do not get somebody driving 600 miles to come to this communities, in his manifesto repeating the very words used by the president of the United States to justify this act of terror and hatred and violence and death."

1 / 4Democratic presidential candidate, former Rep. Beto O'Rourke, greets supporters during a campaign re-launch on August 15, 2019 in El Paso.(Sandy Huffaker / Getty Images) 2 / 4Democratic presidential candidate Beto O'Rourke and his wife, Amy, arrive at a campaign re-launch on August 15, 2019 in El Paso.(Sandy Huffaker / Getty Images) 3 / 4Beto O'Rourke puts on an "El Paso Strong" bracelet during a campaign re-launch on August 15, 2019 in El Paso, after an attack at a Walmart left 22 people dead.(Sandy Huffaker / Getty Images) 4 / 4Beto O'Rourke speaks at a campaign re-launch on August 15, 2019 in El Paso, Texas. O'Rourke paused his campaign after a shooting at a local Walmart targeting Latinos left 22 people dead.(Sandy Huffaker / Getty Images)

On Saturday night, he will appear at a Democratic dinner in Little Rock, putting him in front of at least 1,000 party activists in one of the states with a Super Tuesday primary.

“Obviously I wouldn’t think that any candidate, especially Congressman O’Rourke, would want to see any benefit from something like this,” said Michael John Gray, chairman of the Arkansas Democratic Party, which recruited O’Rourke months ago to keynote the dinner. But he said, “It has increased his visibility ... because of how he has handled the situation. He has been genuine.”

“He’s running for president of the United States. At some point there was going to be his first event after El Paso,” Gray said.

Unlike nearly two dozen 2020 rivals, the former three-term congressman skipped the Iowa State Fair last weekend, along with a gun control forum in Des Moines hastily organized after the El Paso killings and a spree in Dayton, Ohio, that left nine people dead hours later.

“You’re not going to see him eating a corn dog when 22 people were just murdered by a terrorist in his community,” said O’Rourke campaign spokesman Chris Evans. “There wasn’t a discussion about it. There wasn’t a calculus about it. He said he was coming home.”

The campaign aims to capitalize on his renewed attention, after months of treading water, his poll numbers stuck in the low single digits. And O'Rourke has decided to use his time drawing contrasts with Trump by going to the sites of Trump policies he finds offensive, deemphasizing the traditional focus on early voting states such as Iowa and New Hampshire.

Last Wednesday, four days after the rampage, Trump put a fresh spotlight on O'Rourke during a visit to El Paso to thank first responders and comfort survivors and next of kin. During a hospital visit, Trump smiled for selfie photos and boasted, inaccurately, about the relative size of the crowd he drew for a rally in February compared with a counter-rally led nearby by O'Rourke.

The same day, ICE agents raided seven poultry plants in Mississippi, detaining 680 migrants. The El Paso shooter told police he had targeted "Mexicans," and O'Rourke and other immigrant advocates viewed the raids as a particular affront. In hindsight, acting Homeland Security Secretary Kevin McAleenan conceded Sunday, "The timing was unfortunate."

The Texan scrapped campaign events planned that weekend in Nevada and California, rushing back to El Paso as soon as he heard about the shooting.

But he didn't exactly hunker down out of sight, even as he suspended ordinary campaign operations.

Since the rampage, O'Rourke has been a regular presence on cable news shows, continuing a self-appointed role as El Paso's ambassador at large to the nation, emphasizing its otherwise low crime rate and denouncing Trump as a "white supremacist" whose rhetoric inspired the killer.

The shooter drove 10 hours from the Dallas area motivated - according to a manifesto he allegedly posted - by a desire to halt a migrant "invasion," a phrase that echoed Trump. He told police that he targeted "Mexicans," though only eight of the 22 victims were Mexican. The rest were U.S. citizens, except for one German.

O'Rourke has appeared at four high school memorials, along with other vigils and events aimed at denouncing gun violence and anti-immigrant hate. He attended one funeral in Ciudad Juarez and others in El Paso. As of Tuesday night, he had paid five visits to each of two hospitals where survivors were recovering.

1 / 5Democratic presidential candidate and former Rep. Beto O'Rourke consoles Antonio Basbo, who was mourning the loss of his common-law wife, Margie Reckard, at a makeshift memorial outside the Walmart in El Paso where a mass shooting left 22 people dead,(Mario Tama / Getty Images) 2 / 5Democratic presidential candidate and former Rep. Beto O'Rourke hugs a woman at a makeshift memorial outside an El Paso Walmart on Aug. 7, after a mass shooting there that left 22 people dead.(Mario Tama / Getty Images) 3 / 5Holding flowers, Democratic presidential candidate Beto O'Rourke is joined by hundreds of people marching to protest gun violence in El Paso on Aug. 4, 2019. (Michael Robinson Chavez / Washington Post) 4 / 5Presidential candidate and El Pasoan Beto O'Rourke prays during the Hope Border Institute prayer vigil Sunday, Aug. 4, 2019 in El Paso, a day after a mass shooting at a Walmart store.(Mark Lambie / El Paso Times via AP) 5 / 5In this image from Beto O'Rourke's Facebook page, the presidential candidate and former congressman meets with a survivor at University Medical Center in El Paso on Aug. 4, 2019, the day after a gunman killed 22 people at a local Walmart.(AP)

In Iowa, Democratic activists readily forgave O'Rourke for skipping the state fair and suspending his campaign. He's gotten props around the country for his handling of the tragedy.

"I feel like he came home because it mattered, and that he should be there. It showed that he genuinely cared about his community," said Gray, the Arkansas party chairman. "Unfortunately through this tragedy, there has been a spotlight shined on Beto and his stance on common-sense gun laws and common-sense reform. I'm cautious to use the word benefit in a situation like this, but it shows his ability to lead in situations like this."

His campaign billed his Thursday morning speech as a "major address."

Aides made clear that he is staying in the presidential race, quashing speculation that his prolonged absence from the trail meant that he might have reassessed his ambitions and priorities since the shooting, or used the interruption as a pretext to abandon a struggling campaign.

The Houston Chronicle issued an editorial Sunday urging him to "Come home. Drop out of the race for president and come back to Texas to run for senator. The chances of winning the race you're in now are vanishingly small. And Texas needs you."

Sen. John Cornyn, who has warned Texas Republicans for months that O'Rourke may yet turn his sights on him, asked donors on Monday to pitch in, lest that day be nearing.

"Mark my words, as Beto's presidential campaign falters, there will be more of this," Cornyn campaign manager John Jackson wrote in an email blast. "The Chronicle and other liberal media, pundits, and the DC chattering class alike will implore Beto to drop out of the presidential race, and instead run for Senate here in Texas."