WASHINGTON — Beto O’Rourke has picked a feud with Sen. Chuck Schumer after the Senate’s top Democrat rejected his call to confiscate assault-style weapons as a nonstarter even within a party eager to curb gun violence.

“Ask Chuck Schumer what he’s been able to get done,” the former El Paso congressman said Thursday night while stumping in Aurora, Colo., where a gunman killed a dozen people at a movie theater in July 2012.

Taking on one of the most powerful figures in his own party has definite upsides for the former El Paso congressman, whose presidential bid has languished for months.

Having staked his campaign on a controversial push for mandatory gun buybacks, he's now fighting a two-front war, tangling simultaneously with the NRA-friendly president and a leader of his own party.

That positions him as an outsider.

It emphasizes the bold stance he took in last week’s debate in Houston, when his “hell, yes” declaration that he would confiscate AR-15s and AK-47s handed the NRA and other Second Amendment defenders the chance to say they’d been right all along in calling Democrats gun-grabbers.

And it gives him a new way to drum up donations.

In an email blast titled “Sen. Schumer is wrong,” the Texan’s campaign cites a recent Monmouth University poll that found 70% support among Democratic voters for mandatory buybacks for assault weapons.

“Look,” the email says, “Beto would support this even if it weren’t popular, because this is about doing the right thing to end our nation’s gun violence epidemic. But the fact is that the vast majority of Democrats do support Beto’s plan — which means it’s time for leadership that embraces bold gun safety reform.”

A woman in CO told me "hell no" she won't give back her AR-15.



I listened, but by her logic: Why shouldn't you be allowed to have a bazooka or a tank?



These are the conversations Congress shouldn't be afraid of—because if we're going to end this epidemic, we need to have them. pic.twitter.com/UJN02kwh6O — Beto O'Rourke (@BetoORourke) September 20, 2019

But many gun control advocates see O’Rourke’s vow as inflammatory, complaining that a push for confiscation could torpedo a consensus they hope is building for universal background checks and measures such as “red flag” laws, which let police take guns from people deemed dangerous by a court.

A rash of mass shootings this summer, including rampages in El Paso and Midland-Odessa that left 29 people dead in August, have ramped up public pressure on Washington to take action.

Schumer has sought to capitalize on the new climate by pushing President Donald Trump and congressional Republicans to accept background checks on all gun sales.

On Wednesday, he insisted that O’Rourke’s call for gun seizures lacks support within the party — which isn’t quite true. Two other presidential contenders, Sens. Kamala Harris and Cory Booker, also support mandatory buybacks, though not with such charged language as the Texan’s.

"I don't know of any other Democrat who agrees with Beto O'Rourke, but it's no excuse not to go forward," Schumer said on a call with upstate New York reporters.

Schumer met with O'Rourke in February, reportedly to lobby him to run for the Senate again in 2020 after his near-miss against Sen. Ted Cruz last year. O'Rourke jumped into the presidential race a month later.

As a House member in 1994, Schumer led the successful push to ban 19 military-style assault weapons, though the ban expired after a decade. In 1993, he was a key player on the Brady bill, which required background checks for handgun buyers; it also required a five-day waiting period before delivery, which went away in 1998 when a federal criminal database became available for instant checks.

Support among Republicans is certainly low for trying to confiscate the 10 million or more assault weapons in circulation.

Trump called O'Rourke a "dummy" on Wednesday for pushing the idea, tweeting that he'd "made it much harder to make a deal" because it "convinced many that Dems just want to take your guns away."

O’Rourke hit back that “the only thing stopping us from ending this epidemic is you & your cowardice.”

A day earlier, Sen. John Cornyn, a Texas Republican, chided O'Rourke for sabotaging progress on gun violence, asserting that he'd "thrown gasoline," setting "back the debate a lot, maybe by not just years but decades."

Many Democrats want to reinstate an assault weapons ban of the sort that expired in 2004 — the one Schumer helped to enact a decade earlier. That ban grandfathered any military-style weapons gun owners already possessed.

During his bid last year to unseat Sen. Ted Cruz, and until the Aug. 3 killings at an El Paso Walmart, that was O’Rourke’s position: ban new manufacture and import of assault weapons, but let people keep guns they already had.

After that attack, he shifted his position to demand confiscation.

He also rewrote his campaign plan, scheduling appearances at sites of mass shootings and hate crimes around the country, rather than sticking mostly to Iowa, New Hampshire and other states in the first month of contests.

That included Colorado, where he crossed paths with, among others, a survivor of another mass murder — the one at Columbine High School in 1999 that left 15 people dead, including the two shooters.

“Ask Chuck Schumer what he’s been able to get done,” O’Rourke told reporters in Aurora late Thursday. “We still don’t have [universal] background checks. Didn’t have them when he was in the majority, either. ... The game that he’s played, the politics that he’s pursued have given us absolutely nothing and have produced a situation where we lose nearly 40,000 of our fellow Americans every year.”

He noted that 49% of Texans support mandatory buyback — one of the more startling findings in a University of Texas at Tyler poll released on Thursday.

The American people are with us on this," he tweeted later. "They're just waiting on Congress to do the right thing."