British terror suspect Babar Ahmad pleaded guilty to two counts of providing support to terrorists, in US District Court in New Haven, Connecticut.
He did not plead guilty to two additional charges that also included conspiracy to injure the property of a foreign government and money laundering.
US prosecutors said that Ahmad and another man, Syed Talha Ahsan, ran a website that raised funds for Muslim militants in Afghanistan and Chechnya.
The two were extradited to the US from Britain last year.
Ahmad faces the possibility of up to 25 years in prison and two to five years' probation.
More top news
The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.