In the final weeks of President Joe Biden’s reelection bid, House Republicans held a substantial lead over their Democratic opponents with a 61% chance of winning the lower chamber, according to polling from the Hill and Decision Desk HQ. That’s now dropped to 56% with Harris at the top of the ticket. 

Additionally, Harris has cut away at former President Donald Trump’s lead in national polling, with the survey showing the vice president with a 56% chance of winning the White House — up from Biden’s 44%. 

Even so, House Republicans are confident they will win control of the lower chamber, even as the polling advantages they boasted just a few weeks ago begin to dissipate. 

“Democrats are on a sugar high. Everybody’s acknowledged that,” House Speaker Mike Johnson (R-LA) said at a campaign event in Minneapolis on Monday. “The little bounce they get out of the convention is always expected, but I think that Kamala Harris is about to be put to the real test.”

That test will also be applied to Democratic lawmakers returning from the DNC who must now adjust to the campaign trail post-Biden, according to GOP strategists. 

“Much of the environment now is framed on Democrats coming home in their post-Biden sugar high,” a former Republican National Committee spokesperson told the Washington Examiner. “But for all of the adulation of Harris, the race is neck and neck, as is the battle for Congress.”

Johnson similarly pushed back on assertions that current polling spells trouble for his conference to maintain, or even grow, its slim majority in the House. While the top GOP leader recognized Democrats’ recent fundraising prowess and polling advantages, the speaker suggested it is only temporary — arguing the final sprint to the election begins after Labor Day.

Ron Bonjean, a GOP political strategist, told the Washington Examiner the holiday will serve as a “reset,” particularly as Harris and Trump prepare for a debate on Sept. 10 that will determine “where things are and where the energy is.”

“It’s a newfound energy because [Democrats] thought they were going to lose all three — you know, the White House and Congress — with Joe Biden, and now they feel like they have a fighting chance,” Bonjean said. “The challenge they have, though, is they have a candidate that has not been tested with a debate or even a media interview. So we have somebody who’s just completely scripted…and she has to go off-script to provide some insight [and] to answer questions from the media.”

That energy has especially been felt in GOP-held districts that Biden won in 2020 where Democrats initially became concerned voters would be less likely to support the president after his lackluster debate in June. Now they are now feeling confident in Harris’s chances. 

“Now that Harris is at the top of the ticket, what I’ve been seeing in district-level polling is that she is performing close to Biden’s 2020 numbers in these districts, whereas before, when Biden was still at the top of the ticket, Biden was dragging and doing significantly worse than he was in these districts in 2020,” Erin Covey, a House analyst with the Cook Political Report, told the Washington Examiner.

Covey noted that Democrats felt “more bullish” about their chances to win the House even with Biden on the ballot, but that optimism has only grown with the new ticket.

“I think Democrats still felt like they had a decent shot at taking back the House, because it looked like their candidates might be able to overperform Biden,” Covey added. “But, you know, I think, obviously, they’re in a much better position with Harris now.”

Democrats have also benefited from a large increase in fundraising since Harris announced her presidential candidacy. After the DNC, her campaign announced a record-breaking haul of $540 million since Biden bowed out of the race on July 21.

Covey said that will come in handy to fight off Republicans, who started off the 2024 cycle touting their members and candidates with higher fundraising numbers than their opponents despite being an area in which Democrats typically excel.

But even with the newfound enthusiasm among Democratic voters, House Republicans remained adamant that Harris’s presence at the top of the ticket would do little to benefit the party in down-ballot races. 

“Actually I think it helps our chances to hold the House. People are very concerned about Kamala Harris and her record. It’s an objective fact if you look at what she has done over her public life,” Johnson said on Tuesday. “Every single American knows they were doing better under that previous administration and that’s why I think President Trump is going to win and that I’m absolutely convinced we’re going to win and grow the House majority.”

That sentiment was echoed by lawmakers running in some of the most competitive House districts, who told the Washington Examiner Harris has “brought very little enthusiasm” to their home cities. 

“I don’t think it changes anything,” said one House Republican running in a toss-up race in New York. “I think in these races in New York, we are regimented candidates with good records and the issues on our side. Our opposition are weak and lack enthusiasm. Other parts of the country, there is probably more of a drastic effect, and that is one that should be identified by the [National Republican Congressional Committee] in order to counter.”

The NRCC has also made recruitment a top priority in the 2024 cycle, especially after a “candidate quality” issue emerged in the 2022 midterm elections that cost the party key seats. Now, Republicans have been focused on creating “an all-star roster of challengers” that will help secure the majority in November. 

“House Republicans prepared for a trench warfare fight for the majority since day 1 of the cycle [by] building a cash advantage for our incumbents, and honing a quality-of-life message that works no matter the district makeup or political environment,” NRCC spokesman Will Rienert said in a statement. 

Even as Democrats acknowledged the so-called honeymoon period would not last long after the DNC, Covey argued it was evidence of underlying momentum that is likely here to stay.

“I think the momentum they’ve had, even if the honeymoon period’s not going to last, that the momentum is real, and that’s going to have a big impact,” Covey said.

In that case, Bonjean said House Republicans should respond by operating “as if they were 90 yards behind and about to lose the majority.”

“The Harris nomination should be a wake-up call for House Republicans and Democrats are energized, and [Republicans] need to be running as if they are way behind,” Bonjean said. “Whether or not they are, they need to sprint through the tape and win every single seat they can.”