Beto O'Rourke raised $3.6 million from April through June, his presidential campaign announced Monday, a more than 60% drop from his $9.4 million first-quarter fundraising haul that reflects stalling momentum in his campaign.

"I won’t sugar coat it: we have work to do, but we have the resources we need to execute our strategy," campaign manager Jen O'Malley Dillon wrote in an email to supporters.

The former Texas representative boasted an impressive $6.1 million in the first 24 hours after announcing his campaign in March, then a record first-day fundraising haul. Former Vice President Joe Biden later surpassed that, raising $6.3 million in the first day of his launch in late April.

O'Rourke launched his presidential bid following national media attention surrounding his failed Texas Senate bid challenging Republican Sen. Ted Cruz in 2018. After a bump in notoriety and attention following his launch, O'Rourke faded in the polls, down from a 9.5% polling average in early April to 2.6% today, according to RealClearPolitics.

About 98% of donations to the O'Rourke campaign were below $200, with an average contribution of $30, his campaign said. The campaign's cash on hand is $5.2 million.

He has nearly 200,000 donors, surpassing the threshold needed for qualification in the fall presidential primary debates. O'Rourke still needs at least four qualifying 2% polls to make those debates. He currently has three qualifying polls, according to a Politico analysis.

Despite lackluster fundraising, O'Rourke's campaign is outwardly optimistic.

"We could have sent emails that said the sky was falling. We could have burned it all down asking for money. We could have had Beto on the phones with every lobbyist in town. That’s not how we operate — and we don’t feel like we need to," O'Malley Dillon said, pointing to efforts to raise money for down-ballot candidates and an an organization to help migrants seeking asylum.

"It’s easy to look at what’s in the press and feel like your work isn’t paying off. I’m here to tell you that it is," O'Malley Dillon wrote, citing his low fundaising during the early quarters of his Senate campaign in 2017 before fundraising peaked in the third quarter of 2018.

South Bend, Indiana, Mayor Pete Buttigieg led the field in second-quarter fundraising with a $24.8 million haul. Former Vice President Joe Biden brought in $21.5 million since his late April campaign launch, Massachusetts Sen. Elizabeth Warren raised $19.1 million, Vermont Sen. Bernie Sanders raised $18 million, and California Sen. Kamala Harris raised $12 million. Other candidates lag far behind the top tier.