House Republicans have even more reason to be worried about the 2018 midterms: Democratic candidates are trouncing them in the race for campaign cash.

Newly released data from the Federal Election Commission shows that at least 55 Democratic candidates in competitive House races are raising more than the Republican incumbents they’re challenging.

More than 80 Democrats running in Republican-held districts had at least $250,000 in cash on hand at the end of 2017, according to the FEC data. Even incumbents were struggling to raise as much as their challengers; more than a dozen Republican incumbents had less cash on hand than their Democratic opponents.

Democrats are touting this as the latest example of grassroots energy and opposition to Trump and the Republicans; many of the donations to candidates and the Democratic Congressional Campaign Committee are small-dollar donations. For example, approximately one-third of the DCCC’s December receipts were donations averaging $18.

The DCCC, for one, is very happy with the numbers.

“Democratic candidates across the country are out-hustling and out-organizing Republican incumbents, many of whom have not faced a competitive challenge in a very long time and are struggling to find those old campaign muscles,” DCCC spokesperson Tyler Law said in a statement.

Democrats have an uphill battle to take back Congress, but these fundraising numbers show they have continued momentum — and plenty of money — on their side.

Diving into the numbers

The special election for former Rep. Tim Murphy (R-PA)’s seat in Pennsylvania’s 18th district is drawing some of the most campaign cash, with Democratic candidate Conor Lamb raising about $558,000 in the fourth quarter, compared to $162,000 by the Republican candidate, Rick Saccone, during that same period.

In Utah’s fourth district, Democratic candidate Ben McAdams outraised the Republican incumbent, Rep. Mia Love, in the fourth quarter, $502,000 to $452,000.

And California’s Republican incumbents are finding themselves in hot water, with 11 Democratic candidates in seven different districts outraising their Republican opponents.

Longtime Rep. Dana Rohrabacher (R-CA), who has been in Congress since the 1980s, is facing two well-funded Democratic challengers, Hans Keirstead and Harley Rouda, who outraised him in the last quarter. Rouda, who raised $626,000 in the last quarter, is the only Democratic candidate in the district with more cash on hand than Rohrabacher.

The DCCC itself had $38.9 million cash on hand at the end of 2017, a record amount. The closest they came to that number was the 2008 election. But the National Republican Congressional Committee also made a record-breaking 2017 haul, with $43.6 million cash on hand.

Still, as Bloomberg’s Bill Allison and John McCormick pointed out, even though the NRCC also had a record-breaking year, about $20 million of that money is destined for administrative costs like the NRCC’s legal and headquarters accounts. That’s because certain amounts from big donors legally can’t be used in federal elections, so it skews the overall fundraising picture.

“The NRCC has raised more than $20 million in money it can’t use to influence elections, but that still counts as money in the bank on its FEC filings,” Allison and McCormick write. “The DCCC has raised less than $5 million for those accounts, meaning more of its money can be spent trying to actually win seats in November.”

To make matters worse for Republicans, there are more empty seats that they’ll have to defend in 2018 as well. Last week, two more prominent Republican congressmen, Reps. Trey Gowdy (R-SC) and Rodney Frelinghuysen (R-NJ), announced they’re retiring at the end of their 2018 terms.

Republicans are leaving the House in droves: So far, 21 GOP House members have announced they’re leaving, while three Republican senators have said the same. They’re leaving a lot of open seats in their wake, which means Republicans will have to spend more money in more districts. It also presents a huge political opportunity for Democrats.

Democratic energy is high — and it’s being reflected in fundraising

There have been plenty of bad signs for Republicans throughout 2017 and the first part of 2018. The first cropped up earlier this year, when the first numbers came out showing the sheer number of Democratic candidates jumping into House races.

Numbers released by the Campaign Finance Institute this fall showed 391 Democratic House candidates had raised at least $5,000. Of that number, 210 Democrats had raised at least $50,000, and 145 had raised at least $100,000. Here’s what those numbers looked like last year.

These numbers are off the charts, compared to past midterms. Since 2003, there has never been this many challengers before the midterm elections. The highest number before that was 78 Republican challengers in 2009, the year before the Republican wave during the 2010 midterms, in which the GOP picked up six Senate seats and 64 seats in the House.

“From the Democratic side, there’s nothing that looked like these numbers, including the 2010 wave,” Michael Malbin, the executive director of the Campaign Finance Institute, said when Vox talked to him last year.

The number of candidates shows that Democrats are energized, but Malbin also cautioned that it wasn’t enough to predict a blue wave sweeping the House in 2018. Instead, it showed that key ingredients for a wave are in place; not only is there intense energy around Democratic candidates, they are also organized, entering races and fundraising early.

Furthermore, Democrats are benefiting more from grassroots enthusiasm and fundraising. Small-dollar donors (defined as people who give $200 or less) gave the DCCC $41.6 million in 2017. The National Republican Congressional Committee, on the other hand, got $9.8 million from small-dollar donors.

These latest fundraising numbers boost that picture — but there’s still a ways to go until November, and a lot of things could happen. Even with good fundraising numbers, Democrats’ polling numbers on the generic ballot have fallen since December, from a lead of 13 points to six.

Still, these latest filings show Democrats have the fundraising chops to carry this energy through November.