House Democrats never thought they were in for a great night on Tuesday, but their scant gains are inspiring new questions about how the party wins congressional elections after several cycles of disappointment.

Front and center, of course, is Donald Trump. How they missed the signs of Trump’s surprise victory will be a bigger question for the entire Democratic Party (and Republicans and the media alike) for months to come. 

But for Democrats at the House level, there are questions about whether they relied too much on Trump to attack Republicans. 

[Democrats Attack GOP Incumbents for Taking Too Long on Trump]

“Whoever suggested that the major Democratic message should be tying candidates to Donald Trump should be drawn and quartered,” said one Democratic strategist who works on House races.

Democrats currently suffer from their biggest House deficit since the 1920s. They gained just six seats — that’s less than half the more optimistic projections going into Election Day. Even a gain of 15 seats would have been half as many seats as the party needed to win the majority, a prospect all but taken off the table going into Tuesday.

Whereas the Clinton campaign argued that the GOP presidential nominee was an anomaly in the GOP, Democrats at the House level have been arguing since the summer — well before their Senate peers — that Trump is representative of all congressional Republicans.

[Even with Trump, Suburban District Is a Reach for Democrats] 

That didn’t work. At least 15 GOP incumbents considered to be vulnerable, especially with Trump at the top of the ticket, survived Tuesday night. A handful of Republican recruits in open seats prevailed over similar attacks. 

Trump’s negatives were largely about Trump, one strategist argued, and it was hard to apply those negatives to incumbents like Minnesota Rep. Erik Paulsen or New York Rep. John Katko, both of whom over-performed the top of the ticket.

And in districts where Trump won, those ads tying down-ballot Republicans to him may have amounted to positive ads for the Republicans.

[As Maine’s 2nd District Goes, so Goes the Nation?]

Iowa’s 1st District offers a sobering example for Democrats. Rep. Rod Blum, a Freedom Caucus member, won by 8 points in a seat that President Barack Obama twice carried by double digits. Blum started off the year on Roll Call’s list of the most vulnerable incumbents. Democrats thought they could put him away easily. But with Trump’s support gaining in his 90-percent white district, Blum’s place on the list had slipped by October. 

And yet, Priorities USA, the Clinton super PAC that aired its sole House ad in Blum’s district, made Trump the focus of its attack. 

House Majority PAC, which works to elect Democrats to House, was one of the biggest players to use this strategy in other districts across the country. 

“Had we seen more accurate numbers of what that turnout looked like, we may have made some different spending decisions and we may not have talked as much about Trump in some of these districts,” said the group’s executive director, Ali Lapp. 

Notably, the victories Democratic did score didn’t have much to do with that Trump strategy. 

House Majority PAC spent big in Minnesota’s 8th District, an area of strong Trump support where Democratic Rep. Rick Nolan only won by winning over some of the GOP nominee’s voters. 

[In Trump Country, Democrats Fight to Defend Minnesota Seat] 

HMP was also instrumental in helping defeat New Jersey Rep. Scott Garrett and Florida Rep. John L. Mica, two moral victories that had more to do with the incumbents’ self-inflicted wounds than any anti-Trump strategy.

And along with Mica’s seat, the other Florida district that Democrats flipped from red to blue was redrawn in their favor in recent redistricting. Former Florida Gov. Charlie Crist knocked off 13th District GOP Rep. David Jolly, an underfunded incumbent with no outside help from Washington Republicans. 

[Don’t Blame Trump for These Imperiled Republicans]

Even New Hampshire Republican Frank C. Guinta, a vocal Trump supporter whom Granite State Republicans had urged to resign after an FEC scandal last year, held on surprisingly late into the night. Democratic former Rep. Carol Shea-Porter only defeated him by a point in a district where Democratic outside groups cancelled their ad reservations weeks ago because they were so confident.

“So much is outside a congressional campaign’s control,” said Democratic consultant Achim Bergmann, pointing to the down-ballot effects of Trump’s victory.

Nebraska Rep. Brad Ashford lost his re-election in a tough Republican district despite working to distance himself from his party and winning the endorsement of pro-business groups like the Chamber of Commerce.

And in several other districts where Democratic incumbents were presumed to be safe, Minnesota Reps. Tim Walz and Collin C. Peterson and New Hampshire Rep. Ann McLane Kuster all had much tighter than expected re-elections. Party strategists agree that Trump’s underestimated appeal lifted woefully underfunded GOP challengers in those districts.