The Fetterman campaign said it raised more than a million dollars in three hours after the debate.
Fetterman's campaign said the haul shows deep grassroots enthusiasm.
There was only one faceoff between Fetterman, the progressive former Braddock mayor, and Oz, the celebrity doctor backed by former President Donald Trump.
Fetterman was off the campaign trail for months after he suffered a life threatening stroke.
In recent interviews and Tuesday night's debate, the Democrat has relied on a live closed-captioning system due to his hearing issues.
Fetterman appeared to have trouble forming some sentences and delivering cogent responses during the hour long event.
He said his campaign was all about fighting for anyone in Pennsylvania who had been knocked down and had to get back up again.
Fetterman warned that the use of closed-captioning could lead to awkward moments and that this isn't John's format.
Brendan McPhillips, Fetterman's campaign manager, said that the people of Pennsylvania have John's back in the race.
There was a huge show of support for John tonight. Heading into the last two weeks of the race, we are grateful for the support.
During the live debate, the candidates were asked about crime, economic and social issues, as well as their own background.
Oz was criticized for saying that local political leaders should have a voice in abortion decisions. The best ideas should be put forward so states can decide for themselves, Oz said.
Fetterman was tripped up when asked to reconcile his previous claims that he has never supported the practice of frack with his current support for it.
The Pennsylvania Senate race has been characterized by an aggressively rancorous tone, with each candidate accusing the other of lying multiple times.
The swing state seat is seen by both parties as a must-win contest in order to control the Senate.
Fetterman and Oz are competing to become the next senator from Pennsylvania. The opening in Pennsylvania, where President Joe Biden beat Trump in 2020, gives Democrats one of their best chances to flip a Republican-held seat and hold onto their razor-thin Senate majority.
The candidates appear to be in a dead heat with less than two weeks to go before Election Day.