HARRISBURG (AP) - Democrat John Fetterman and Republican Mehmet Oz will meet tonight for one of the most highly anticipated debates of the midterm elections as they wage a fierce contest for a U.S. Senate seat from Pennsylvania that could decide control of the chamber and the future of President Joe Biden’s agenda.

Much of the focus is on Fetterman, who has spent the past several months fending off an escalating series of attacks from Oz about his health and fitness for office. Fetterman, who is Pennsylvania’s lieutenant governor, had a stroke in May, a health scare that was so severe he said he “almost died.”

But he has insisted he is prepared for the demands of the Senate. Since his stroke, Fetterman has struggled at times to speak clearly in public events. Independent experts consulted by The Associated Press, however, said he appears to be recovering remarkably well. He will use closed-captioning during the debate to help him process the words he hears.

Still, Tuesday’s debate could prove to be a decisive moment in a race that represents the best chance for Democrats to flip a Republican-held Senate seat this year. It will provide an opportunity for Fetterman to prove that he has the stamina for the job and shift the focus to Oz, who Fetterman has argued is a carpetbagger from New Jersey with no understanding of the state. Oz, meanwhile, will have a high-profile chance to unite Republicans and appeal to moderates who could decide the race.

The high-stakes debate - the first and only in the contest - comes just two weeks before Election Day in what polls say is a close race to replace retiring two-term Republican U.S. Sen. Pat Toomey. It’s the only major statewide debate happening this year in Pennsylvania since Democrat Josh Shapiro and Republican Doug Mastriano couldn’t reach an agreement on terms for a gubernatorial debate.