Ahead of Tuesday's presidential debate, Democratic nominee Joe Biden is leading President Donald Trump in the key battleground states of Georgia and Pennsylvania, according to polls released on Tuesday.

A Quinnipiac University survey shows Biden leading Trump by 3 points in Georgia, 50% to 47%. The poll of 1,125 likely voters was conducted from Sept. 23-27, with a margin of error of 2.9 points.

Trump won Georgia in 2016 but Hillary Clinton had narrowed the margin of victory from 2012. The last time a Democrat won Georgia was in 1992, when Bill Clinton narrowly defeated incumbent Republican President George H.W. Bush in a race that included independent Ross Perot.

"It was Trump by 5 points in 2016 but it's a nail biter in 2020. Can Biden be the first Democrat since Bill Clinton to turn Georgia blue?" Quinnipiac polling analyst Tim Malloy said about the survey.

Biden has maintained a solid lead over Trump in Pennsylvania, another crucial battleground state. A Washington Post/ABC News survey released Tuesday showed Biden with a 9-point lead over Trump, 54%-45%.

The Pennsylvania survey of 567 likely voters was conducted from Sept. 21-26, and has a 5-point margin of error. The poll shows Biden leading Trump by more than 2-1 in Democratic stronghold Philadelphia and its surrounding suburbs, with Trump faring better in the middle parts of the state.

Trump pulled off an upset win over Hillary Clinton in Pennsylvania by a slim 0.72% margin, 48.1% to 47.4%. Pennsylvania, which has 23 electoral votes, had been considered a "Lean Blue" state in 2016.

Biden, who was born in Scranton, is considered the favorite to win Pennsylvania in 2020. Poll aggregator Real Clear Politics shows Biden with an average lead of 5.7 points. The last poll to show Trump leading in Pennsylvania was in late-May.

Recent general election polls show Biden with a nationwide lead over Trump. A recent Monmouth survey showed Biden with a 5-point nationwide edge over the incumbent, 50% to 45%.

According to the Commission on Presidential Debates, the topics Tuesday are the records of the two candidates, the Supreme Court, the COVID-19 pandemic, the economy, race and violence in cities, and the integrity of the election.