But while he was able to stand out in his Senate campaign with a broadly liberal message and no signature policy issue, that broad message is not likely to be enough in a ballooning Democratic field.
This time, the specifics are going to be crucial. Here’s a look at where O’Rourke stands on some major issues.
Immigration
As President Donald Trump’s proposed border wall has become one of the biggest issues in U.S. politics, O’Rourke has made immigration the centerpiece of his speeches.
In addition to supporting the DREAM Act and a path to citizenship for immigrants who are living in the country illegally, he has called for the closing of private immigrant detention centers, denounced the “militarization” of immigration enforcement and spoken out against the wall.
“We are not safe because of walls but in spite of walls,” he said at a rally in El Paso last month held at the same time Trump was holding his own rally nearby. Far from extending a barrier across the entire border, he has said, he would like to remove the existing fencing in El Paso — one of the country’s largest border cities, and O’Rourke’s hometown.
In his State of the Union address, Trump held up El Paso as an example of the need for a wall, claiming that the city had been one of the most dangerous in the United States until a border fence was built there.
But the crime rate in El Paso actually fell long before the fence was built and rose afterward, and O’Rourke is holding up the city as an example of the lack of need for a wall.
Gun control
O’Rourke arguably first made his name when, after the shooting at the Pulse nightclub in Orlando in 2016, he livestreamed the sit-in he and other Democratic representatives were holding on the House floor in support of stricter gun laws.
The Republican-controlled Congress did not pass any gun control legislation then, but O’Rourke continues to support similar policies, including universal background checks, magazine size limits and restrictions on some semi-automatic weapons.
He also opposes concealed carry reciprocity, which would make concealed carry permits granted in any state valid nationwide, forcing states with strict licensing requirements to recognize permits from states with looser standards. It is one of the National Rifle Association’s legislative priorities.
Health care
While O’Rourke supports universal health care — increasingly a litmus-test position for Democratic candidates — he hasn’t committed to a specific way to get there. During his Senate campaign, he suggested that universal health care could take the form of a single-payer system or “a dual system,” in which a government-run program would coexist with private insurance.
He has given conflicting messages on the most prominent proposal, “Medicare for all.”
In 2017, during his time in the House, he said unequivocally, “A single-payer ‘Medicare for all’ program is the best way to ensure all Americans get the health care they need.” But during his Senate campaign, he carefully avoided those words, calling instead for “universal, guaranteed, high-quality health care for all.”
He does support expanding Medicaid under the Affordable Care Act and has urged Texas to do so. Other points in his 2018 platform included allowing the government to negotiate prescription drug prices with manufacturers and creating incentives for insurers to participate in the Affordable Care Act’s exchanges.
Climate change
When it comes to proposals for mitigating climate change, opponents frequently cite the potential costs of those plans. But O’Rourke has emphasized the financial impact of climate change itself. Billions of dollars that are spent on steps like sea walls, which would be critical if climate change continues unchecked, is money not spent on other priorities, he noted at a town-hall event with Columbia University students last month.
At that event, O’Rourke spoke positively about the Green New Deal, calling it technically and logistically doable. As for its political prospects, “I don’t know,” he said. “That’s up to all of us, right?”
He supports the Paris climate accords, and has also made a point of emphasizing effects that climate change is having: more storms like Hurricane Harvey, for instance, which devastated Texas.
Criminal justice
O’Rourke emphasized criminal justice in his 2018 campaign, focusing in particular on racial and economic inequities. In an op-ed in The Houston Chronicle, he described his own criminal record — he was arrested once for attempted forcible entry and once for drunken driving when he was in his 20s; both charges were dismissed — and argued that his success since then had been possible because of his race and economic status.
“The chance that I had, and which I have made the most of, is denied to too many of our fellow Texans, particularly those who don’t look like me or have access to the same opportunities that I did,” he wrote.
He called for closing private and for-profit prisons, decriminalizing marijuana and expunging the records of people previously convicted of possessing it, eliminating mandatory minimum sentences for nonviolent crimes, and reforming the bail system so people charged with misdemeanors would not be incarcerated because of their inability to pay.
He also emphasized rehabilitation for offenders released from prison, including the restoration of voting rights. Currently, those rights vary drastically by state.
Trade and agriculture
Like many of the Democratic candidates, O’Rourke has criticized Trump’s trade policies, including the imposition of tariffs, which have hurt some farmers and blue-collar workers. In his Senate campaign, he emphasized the needs of farmers, calling for a stronger crop insurance program and federal investments in rural infrastructure, including high-speed internet, roads and schools.
He has also drawn connections between agricultural policy and immigration policy, noting that immigrants — many of them undocumented — make up a large share of farm laborers. On that basis, he has cast immigration reform as an economic issue as well as a social one.
“We should treat these individuals with dignity and respect,” he wrote on his website last year, “because they are a critical component of our agriculture communities.”
This article originally appeared in The New York Times.