Republicans have struggled mightily at the ballot box since Donald Trump took office. They lost a U.S. Senate seat in dark-red Alabama last December and a House seat in heavily conservative western Pennsylvania earlier this month. In those races, the usual rhetoric about abortion and immigration did little to buoy Republican candidates, and even a recent tax cut failed to rally GOP voters. So, to reverse that trend, Republicans are turning back the clock to 2016.

The National Republican Senatorial Committee on Monday unveiled a new ad campaign that focuses on—who else?—Hillary Clinton. The ads hope to use the former presidential candidate as a weapon against 10 Senate Democrats up for re-election in states that went for Trump two years ago. The ads, which the NRSC says will run on Facebook for two weeks, highlight a pair of remarks Clinton made about Trump voters that she felt compelled to later walk back: her “basket of deplorables” comments last year and similar ones she made this month about Trump appealing to voters by “looking backwards.”

“She’s called you ‘deplorable,’ ” the ads declare. “Now she’s called you ‘backwards.’ ” The state-specific spots then go for the kill by reminding viewers that their home-state senator backed Clinton over Trump in 2016.

Even after 25 years and two failed presidential campaigns, Clinton remains a bête noire of the conservative establishment. Trump makes frequent, near-compulsive mention of her on his Twitter account. House Republicans have done all they can to keep alive her past scandals, both real and imagined. And conservative media rarely misses the chance to make Clinton a foil for the president.

This marks the first time this cycle that the NSRC has featured Clinton in one of its ads, and the attack echoes one made by Josh Hawley just last week in Missouri as part of his bid to unseat Sen. Claire McCaskill there. The ads could help test how much potency the Clinton name still has with voters, two years after her name was last on the ballot. At the very least, it makes for an uncomfortable wedge issue for Democrats in red states, who may risk alienating some of their own voters as they try to distance themselves from Clinton.

To see how awkward this dance can be, just watch McCaskill’s appearance on MSNBC last week. Asked if Clinton’s comments were helpful to her, McCaskill said, “No, probably not” and then defended Missourians who voted for Trump. “For those of us that are in states that Trump won, we would really appreciate if she would be more careful and show respect to every American voter and not just the ones who voted for her,” McCaskill said.

Clinton has somehow become even more unpopular since the campaign ended, giving Republicans hope that reminding Trump-inclined voters just how much they hate her will close the enthusiasm gap with Democrats, who have found special-election success, at least in part, by harnessing the anti-Trump resistance. It wasn’t that long ago, mind you, that nearly half of Trump supporters said their primary motivation was not putting Trump in the White House but instead keeping Clinton out of it.

At the same time, Trump’s approval rating has ticked back up into the 40s—still dismal, yes, but up from the historic lows of his first year in office—while the Democratic lead in the generic congressional ballot has been eroding lately. A new Fox News poll, taken during the first half of last week and released Sunday, found Democrats up just 5 percentage points on Republicans, 46 percent to 41 percent. That’s quite the drop from the 15-point cushion they had in the same survey back in October.

While the phrase Fox News found doesn’t necessarily instill confidence on its own, the conservative cable network’s pollsters are well-respected in their field, and their latest findings line up with the major polling averages, which have a generic Democrat up between 5 and 6 points on a generic Republican. That’s about as small as the gap has been at any point this year and less than half what it was at the start of it. Making matters worse for Democrats is that partisan gerrymandering, geographical quirks, and the advantages of incumbency tilt the House playing field in the GOP’s favor considerably. By some estimates, they’ll need to win by somewhere in the neighborhood of 5–8 percentage points nationally to flip the House.

The odds are even longer in the Senate, where Democrats need to gain two seats to take control of the upper chamber. That seems easy enough until you remember there are only nine GOP seats up in November, four of which look about as safe as they can get. Campaign handicappers currently believe that, at best, there are only three places Democrats have a legitimate chance to pick up a seat: Arizona, Nevada, and Tennessee. But that’s only half of the equation; Democrats also need to protect the 26 seats they have that are up in the midterm, as many as seven of which are expected to be competitive. If Republicans can use Clinton to pick off a vulnerable Democrat or three in states Trump won, they could put control of the Senate safely out of reach.

Put another way, then, Democrats could significantly outperform Republicans on Election Day and yet still fall short of what they are hoping to accomplish in November. Now that is something Hillary Clinton can tell them all about.