Meanwhile, swing-district Democrats are receiving little reinforcement from their own party or even other liberal coalitions. Democratic and pro-impeachment groups have spent about $2.7 million in TV ads, according to an analysis of spending by the ad tracking firm Advertising Analytics. And more than $600,000 of that total went to ads targeting Republican incumbents, not helping vulnerable Democratic members.

"Many of us have been expressing our concerns to leadership," said a Democratic lawmaker said, who declined to be named in order to speak candidly about strategy. "You don’t want to have to play catch up."

“Everyone knows you don't just take a shot and sit there,” the lawmaker said. “It’s like someone taped our arms to our side and punched us in the face.”

Some Democrats raised the spending disparity during a closed-door meeting with Speaker Nancy Pelosi and her leadership team on Wednesday. One moderate Democrat asked if party officials planned to launch more ads, particularly in more rural swing districts in less expensive media markets where incumbents are desperately looking for more air cover, according to multiple people in the room.

Democratic-aligned groups, however, have begun spending on ads. Last week, the liberal coalition Protect Our Care launched a $2 million digital ad campaign to promote a Democratic drug-pricing bill. But GOP groups are devoting far more cash, including a roughly $5 million buy on anti-impeachment TV ads across 18 Democratic districts by American Action Network, a nonprofit tied to House GOP leadership.

It’s uncommon to see such enormous spending more than a year out from an election — marking a significant ramp-up in the public battle to shape the politics of impeachment.

And there are more: A pro-Trump group called Presidential Coalition, backed by conservative force Citizens United, announced this week that it’s spending more than $1 million on TV ads in the districts of Brindisi, Joe Cunningham (D-S.C.), Ben McAdams (D-Utah), Elissa Slotkin (D-Mich.) and Xochitl Torres Small (D-N.M.).

Then there's the big spending by Trump’s reelection team, which announced $10 million in spending on television and digital ads just days after House Democrats formally declared their impeachment inquiry in September.

Asked about the largely unanswered onslaught of GOP attack ads, most Democratic moderates publicly dismiss concerns with the party’s strategy.

“That’s probably something for the pundits to decide. I’m just focused on doing the right thing and voting for the district,” Cunningham said in an interview. “People in the First District are smart and they can sift through the fiction and get to the facts and when they do they realize that I’m the most bipartisan freshman Democrat.”

McAdams, another swing-district Democrat who’s being targeted by ads, said he’s working to counter the GOP ads with his own direct pitches to voters in events like town halls.

“They’re negative but you know, I’m out there in person telling my district the work that I’m doing and they know me,” McAdams said. “They’re going to judge me based on who I am and my track record and I think I have a track record that resonates.”

Democratic officials and strategists are debating how best to defend their incumbents that are crucial to keeping the House majority as the impeachment furor consumes Capitol Hill.

Some say Democrats are already earning free media from the wall-to-wall coverage of this month’s impeachment hearings, which they believe has been largely good for their party and hurtful for Republicans.

And they say any TV ads so early in the cycle would do little to sway voters. Instead, they argue GOP spending is more of an attempt to get Democrats to spend big with almost a year left to go.

“It’s not about changing voters’ minds. It’s about pressuring Democrats,” one Democratic national strategist said.

But there are others who argue that Democrats — both official party organs and affiliated groups — need to be more aggressive in pushing back against the GOP’s narrative, especially for voters who aren’t following the impeachment coverage on CNN or MSNBC.

They look at groups like Need to Impeach — which was a thorn in the side for Democrats for months on impeachment — and how it is spending big to win over GOP support that may never budge.

This week, for example, Need to Impeach spent $40,000 on a new ad targeting Senate Majority Leader Mitch McConnell in Kentucky, a seat that has been solidly red for decades.

Another coalition backed by national security and veterans groups, Defend American Democracy, released a six-figure ad buy to pressure vulnerable Republicans in 14 districts. But so far, it hasn’t spent on a single Democrat.

House Majority Forward, a nonprofit with ties to Pelosi, has so far made the largest investment to help vulnerable Democrats, running $2 million worth of ads in a dozen districts. Those spots touted legislative achievement of freshman lawmakers but did not explicitly mention impeachment.

The group declined to share more details of their ad strategy, including when they might launch more.

“We are committed to expanding and protecting the Democratic House majority and will continue to highlight the issues that matter most to American families,” spokeswoman Caitlin Legacki said.

At least one moderate Democrat has launched her own ads in support of her impeachment position: Rep. Elaine Luria (D-Va.), a former Navy officer who released a $5,000 digital ad on Veterans Day that earned high praise from others in her caucus.

But few others are expected to follow suit. In interviews, several freshman Democrats suggested it was too early to counter with their own advertising.

Still, top House Republicans insist Democrats’ impeachment inquiry will repel voters in key swing districts next November. Already, GOP strategists say it has been a boon to their fundraising and candidate recruitment.

“The new socialist Democrat majority in the House literally gave away its majority the day it started this impeachment proceeding,” Rep. Tom Emmer said.

Zach Montellaro contributed to this story.