Behind closed doors and in public appearances, GOP leaders are raising the alarm over the commanding monetary lead Democrats have built up as November’s election inches closer.

Democrats had an advertisement spending advantage in nearly every competitive Senate race as of August and the Congressional Leadership Fund, the primary super PAC aimed at electing Republicans to the House, is $70 million behind its Democratic counterpart in ad spending, according to Politico. The situation has high-ranking Republicans making public and private pleas to big-dollar donors in an attempt to close the financial gap before voters head to the polls in November.

“Right now, the left-wing billionaires are massively outspending us,” Republican Montana Sen. and National Republican Senatorial Committee (NRSC) Chair Steve Daines said in his July Republican National Convention speech. “That’s what’s keeping me up at night.”

Daines ended his speech by appealing to listeners to go to a Republican fundraising website and donate to the party’s effort to retake the Senate.

Congressional Leadership Fund President Dan Conston, meanwhile, said at the GOP’s mid-August Jackson Hole retreat in Wyoming that, while he felt good about some key House races, his organization needed an additional $35 million to keep the Democrats at bay, Politico reported.

Republican North Carolina Rep. Richard Hudson, chair of the National Republican Congressional Committee (NRCC), also agreed that the deluge of Democratic fundraising spells trouble for the GOP, according to Politico. Hudson and Conston told donors at the Wyoming retreat that the total gap between Republican and Democratic candidates in battleground races was roughly $37 million.

On the Senate side, Republicans trailed Democrats in Arizona by $57 million in terms of ad spending, while Democrats maintained $41 million ad spending leads in Wisconsin and Nevada, according to Politico.

“Money can’t buy you love, but it can influence the outcome of an election,” NRSC executive director Jason Thielman told the Daily Caller News Foundation.

“The only thing preventing us from having a great night in November is the massive financial disparity our party currently faces,” he continued. “We are on a trajectory to win the majority, but unless something changes drastically in the next six weeks, we will lose winnable seats.”

Republican parties in the key states of Arizona, Wisconsin and Minnesota were also massively outraised and outspent by their Democratic counterparts in the most recently released wave of campaign finance disclosures.

It’s not all bad news for the GOP, as Republican David McCormick and aligned groups have a $30 million advantage over incumbent Democratic Pennsylvania Sen. Bob Casey and former Maryland Gov. Larry Hogan and his allies lead Democratic nominee Angela Alsobrooks by $9 million in the race for the state’s open Senate seat, according to Politico. Casey, however, has a commanding lead over McCormick in the polls, with the incumbent senator ahead of his Republican challenger by 6.5 points in Real Clear Polling’s average of polls.

Hogan and Alsobrooks, however, are neck and neck in deep-blue Maryland, according to recent polling.

“When Republicans have the resources to tell this story, we win,” NRCC spokesperson Jack Pandol said, according to Politico. “We just can’t allow a green tsunami of Democratic cash to change the conversation from the issues.”

The NRCC and Congressional Leadership Fund did not immediately respond to the DCNF’s requests for comment.