In a heated debate on Thursday, President Joe Biden and his Republican rival, Donald Trump, exchanged sharp personal insults and policy criticisms. The two candidates, the oldest in U.S. history, clashed on issues such as abortion, immigration, the economy, and their respective records in office.

Biden’s performance was marred by noticeable faltering and a hoarse voice, which his allies attributed to a cold. This shaky presentation has heightened concerns among Democrats about his age and ability to serve another term. A prominent Biden donor described his performance as “disqualifying,” hinting at potential calls for him to step aside before the Democratic National Convention.

Vice President Kamala Harris defended Biden, emphasizing his overall presidential record over the past three and a half years. Despite a slow start, Biden attacked Trump on various fronts, including his conviction for hush money payments and the lack of endorsements from his former cabinet members.

Trump, meanwhile, repeated several unfounded claims and criticized Biden’s handling of the southern border and the economy. The debate, held on CNN without a live audience, was characterized by mutual disdain and frequent interruptions, with each candidate labelling the other as the worst president in history.

Polls indicate a tight race, with significant voter dissatisfaction and concerns about both candidates’ fitness for office. The next debate is scheduled for September.