The new senator needed to hire staff to work in his new office, and after an interview with a then-young Joe Biden, the Delaware Morning News reported that the ideal job applicant would be one who shared his opposition “to such liberal shibboleths as gun control.”

In 1973, Biden described himself as “really liberal to moderate,” and the newly minted lawmaker destined to become vice president decades later would even say during that same interview that he was a “social conservative.” His early time in the Senate shows as much.

Biden earned favorable grades from the NRA during his first two terms -- solid B’s in 1978 and 1984. He accepted campaign contributions ahead of his second election from the original manufacturer of the AR-15, Colt Industries. He voted to allow the interstate sale of handguns, successful legislation that the press heralded in 1985 as “a major victory for gun owners, dealers and the National Rifle Association.”

And yet, Biden has as sterling of a gun control reputation as any of the candidates competing for the Democratic nomination in 2020, if not better. He helped pass gun control legislation when Mayor Pete Buttigieg was in middle school, then followed up on his work in the Senate during his two terms in the Obama White House.

All of this allows the former vice president to say with confidence, as he often does, that he took on the NRA twice, and won. Now, as the pro-gun Democrat of the 1980s goes extinct and a more confident gun-control party emerges, Biden hopes his record will help make him president.

The front-runner released a detailed gun control agenda in October, drawing on his decades of experience: Ban the assault weapon. End the high-capacity magazine. Launch a federal buy-back program for newly banned firearms. These are just some of the top priorities that a Biden presidency would try to work into law.

One thing was left out.

“I’m so tired of people talking about your prayers,” Biden said last week at a California event about 45 miles south of Santa Clarita, where the latest school shooting took place. “Damn it, we have to protect these kids. We have to do it now.”

If anything, the famously friendly politician has become more aggressive and impatient. He complains that Canadian geese get more protection than American schoolchildren. He regularly lambasts the gun lobby. He labels gun manufacturers, including a former donor, “the enemy.”

This is a far cry from previous Democrats who thought they had to send mixed messages, the enduring image being John Kerry dressed up in camouflage and toting a 12-gauge shotgun as he posed with four dead geese in a carefully choreographed photo op on Ohio farmland two weeks before the 2004 presidential election. The campaign was trying to show that the candidate, who supported gun control, supported hunters. It didn’t work.

Democrats would lose that state and the White House -- and Bob Shrum, a senior adviser to Kerry’s campaign, would later acknowledge that putting the nominee in camo was a mistake. “I wouldn’t recommend doing that today,” he told RealClearPolitics, “Indeed, I didn’t recommend doing it at the time.”

It isn’t that Democrats no longer say they’re pro-hunting anymore. According to Shrum, it is that everything else has changed: “Substantively, I don’t think there was that much difference between then and now. The big difference is obviously the politics of the issue. It was a much tougher issue in 2004 than it is in 2019 and heading into 2020.”

Not long ago, powerful Democrats publicly urged their colleagues to avoid the gun issue. After announcing his retirement from the House, famed Massachusetts liberal Barney Frank said it was a mistake “to insist that every Democrat be for gun control.” In December 2011, Frank said gun control was “a great loser for us in most of the country.”

A year later, almost to the day, a shooter killed 20 children and six adults at Sandy Hook Elementary School in Newtown, Conn. Horrific mass shootings followed in Orlando, Las Vegas, El Paso and numerous other American cities. They would all be galvanizing, prominent Democrat Matt Bennett told RCP, if there weren’t so many.

The carnage hasn’t swayed primary voters as much as it’s moved their kids. “The thing that has brought this into focus most sharply,” said Bennett, a veteran of the Clinton White House, “is that almost every child in the United States goes through lockdown drills now, and they go home to tell their parents, who are confronted with the idea that someone could come into their child’s school and shoot them.”

Aggressive reform has subsequently become canon in the Democratic Party. Gun control regularly ranks as a top concern among the primary electorate: Ahead of the Houston primary debate in September, a Morning Consult/Politico poll found 73% of Democrats said it was “very important” to hear the candidates speak on the issue -- and they have done so. To a person, each of the presidential hopefuls supports stringent changes to federal laws, evidence, Robin Lloyd told RCP, of the fact that this is the most pro-gun-control field in recent history.

“The fact that we have so many candidates running for president on the Democrat side and they are all champions of gun safety and of addressing the gun violence epidemic of this country is a watershed moment,” said Lloyd, the managing director of the gun violence prevention organization founded by former Rep. Gabrielle Giffords.

While the Biden campaign would likely bristle at the suggestion that he has evolved on gun control over the years, other candidates have changed in real-time. Montana Gov. Steve Bullock won his seat on a promise to oppose universal background checks in 2016. Then he became a presidential candidate and decided to support what he once condemned. Not so with the former vice president.

Every veteran campaign hand and every advocate and every operative who spoke to RCP described Biden as the gold standard of gun control. His resume goes back decades. He is the guy who helped push through the Brady Handgun Violence Prevention Act in 1993 and the guy who got the assault weapons ban to the finish line in 1994 and the guy who quarterbacked the Obama administration response to gun violence in that president’s second term.

“The Joe Biden credentials on gun safety are as rock-solid as anyone’s on the planet,” Bennett said, “notwithstanding some stuff that he might have said and done in the ’70s.”

This legislative record will be the selling point in the ideal scenario of the Biden campaign. Some believe that grabbing guns could give Biden another chance to grab the spotlight. “There is an absolute opportunity,” Bennett said, “and I hope that he does take it because this is really something without puffery or inflating he can actually claim an appropriate amount of credit for the things we’ve done on guns.”

The years of crusading, minus the early period of moderation, could become the blueprint for year one of the administration of a vice president turned president, if he wins. And there is much work to be done, those on the left say. Come 2021, given a Democratic Senate, they expect Biden to put in place what he advocated for throughout his career. Except, of course, what he backed at the start.