As Democratic operatives gathered in Philadelphia for a triumphant convention last week, allies of Donald Trump were moving to undercut Hillary Clinton. The super PAC Rebuilding America Now started airing an attack ad called “Outsourcer” in key swing states from Florida to Pennsylvania, claiming that Clinton, in a speech behind closed doors in New Delhi, had said she would not combat outsourcing. The ad also claims she accepted $1 million in donations from Indian donors in 2008. “The outsourcing will continue,” she says in one of the spliced-together clips, with Indian music playing in the background.

According to The New York Post, the Clinton campaign pressured TV stations to pull the ad, arguing that public records show the opposite of what the ad claims. But campaigns rarely succeed in getting ads removed from airwaves, even when the commercials make outlandish, unsubstantiated claims. So the Clinton campaign tried a more reliable method of punching back at Trump: An attack ad using Trump’s own words against him.

In it, David Letterman brandishes a handful of silky Trump ties with pink and purple stripes, quizzing the billionaire on where they were made. “Now, these ties,” Letterman says in “Someplace,” the commercial the Clinton campaign released Wednesday. “Where are these ties made?” Trump replies: “We employ people in Bangladesh. They have to work, too.”

This first volley of attack ads could seem like typical campaign banter. But it highlights a deeper problem for the Trump campaign. Not only does Hillary Clinton have her own arsenal of attacks, but she can also dust off old clips of Trump indicting himself. The icing on the cake is that many of these clips, like the one of David Letterman, surfaced in the Republican primary and are just waiting to be introduced to a wider audience in the general election. 

Since last year, the Clinton campaign and its allies have been compiling dossiers of damning material on Donald Trump. Strategists at Priorities USA Action, the Democratic super PAC that serves as Clinton’s main attack dog, told me their team has been collecting opposition research on Trump since last winter.

In the subsequent months, Republicans vying to take Trump down in the primary gave added ammunition to the Democrats. The David Letterman clip first surfaced in an ad called “Outsourcer” paid for by Out Principles PAC, a Republican group that worked to stop Trump from getting the nomination. It was lost in the glut of advertising flooding Ohio in the run-up to its March 15 primary. But now, the charges feel like they stick. The interview is pretty damning—and it effectively shuts down any notion that Clinton is the candidate actively promoting outsourcing.

This gives Clinton a massive advantage. There were all sorts of attacks in the primary that have yet to be used against Trump in the general: his alleged ties to the mafia, for one. In an ad that aired in Florida on March 2, the announcer says: “Trafficking convictions. Prior mafia ties. This isn’t a drug cartel; these were Donald Trump’s business associates.”

Then there are the single moms and retirees tearfully recounting on camera how Trump convinced them to sink their savings into a real estate course that turned out, they said, to be a scam. The Trump University salesman, Cliff, who talked about how his bosses drove Bentleys and Aston Martins, while the students spent hours on the phone trying to find out where their money had gone. Vera Coking, the little old lady Trump forced from her modest Atlantic City home to make way for a limousine parking lot outside his now-defunct casino. Dozens of people who lost money after they invested in Trump Tower Tampa, which later went bankrupt. Clinton can mine any of these ads from the Republican primary for material to hit back at Trump if and when he decides to attack her next.  

Furthermore, according to NBC News, her campaign and its allies have reserved $98 million in advertising time through the fall. The next time Trump or his allies attack, Clinton’s team can slap together a rebuttal in less than a week and sub it into their standing ad buy in key swing states around the country, just as they did this week. 

Rebuilding America Now will find it hard to overcome that kind of advantage. The group was founded just two months ago, aided by private equity investor Tom Barrack, a longtime friend of the Trump family. It has hired a smattering of Republican operatives and ad pollsters to flesh out its nascent operation. Still, they may not have much material to work with. The Democratic primary surfaced very little damning material on Hillary Clinton that was new to voters. Bernie Sanders rarely attacked her by name.

The Republicans have yet to learn the importance of keeping their primary civil. Mitt Romney fell into the same exact trap in 2012. In January of that year, after a cash infusion from billionaire casino mogul Sheldon Adelson, Winning Our Future, a super PAC that backed Newt Gingrich in the Republican primary, released attack ads drawn from its savage documentary King of Bain: When Mitt Romney Came to Town. The Democrats used the footage of people Romney had laid off to great effect in the general election.

Trump is about to feel the same pain. Clinton will likely continue to cherry-pick choice attacks from the Republican primary. She’ll lob them out when provoked and let Trump do the rest of the work for her. In the space of a couple of weeks, he has insulted a gold star family, ejected a baby from a rally, and called on Russia to hack his opponent—all as his polling numbers tanked, erasing the bump he got during the Republican convention. Politicians rarely find themselves in as strong a position as Hillary Clinton does now, with a readymade arsenal of attacks that she need only use sparingly.