PHILADELPHIA (NewsNation Now) — Former President Barack Obama made his debut on the campaign trail for the man who helped him lead the country for eight years, Joe Biden.

Obama’s visit to Philadelphia Wednesday marks his first in-person 2020 campaign event for Biden, his former vice president and the current Democratic presidential nominee. Obama hosted a drive-in car rally, where supporters listened to him over their radios.

The former president urged Americans to vote and vote early if possible. He spoke to President Donald Trump’s management of the pandemic, the president’s taxes, and his alleged “secret Chinese bank account.”

Obama reminded Americans of the seriousness of the COVID-19 pandemic. “This is not a reality show, this is reality,” Obama said.

Obama said the country has had to live with the consequences of Trump “proving himself incapable of taking the job seriously.” He said, “America’s proud reputation around the world is in tatters.” He backed Biden and Harris for the presidency and promoted their plan for stabilizing the economy and coronavirus pandemic response.

With just 13 days until the presidential election, both political parties have focused heavily on Pennsylvania. Trump opted for a rally in the state Tuesday instead of formal debate practice, while Obama’s visit underscores the significance of the battleground state that Biden himself has visited the most this campaign. Democrats narrowly lost the state to Trump in 2016.

“If we win Pennsylvania, we win the whole thing,” Trump said at the rally in the northwestern city of Erie Tuesday night.

According to a NewsNation/Emerson College poll of Pennsylvania earlier this month, Biden held a 5-point lead, but Trump wasn’t far away from closing the gap.

Trump will spend the day campaigning in North Carolina, where Biden’s running mate Sen. Kamala Harris will also visit Wednesday. Vice President Mike Pence will speak in New Hampshire and Ohio.

Obama’s involvement in campaigning for Biden has focused in part on getting younger Americans to vote. He’s appeared on Twitch, the video game streaming platform, pushed a voter registration message on Snapchat and recorded a video for the Shade Room, a Black-owned Instagram page and media company with 21 million followers.

“President Obama has been appearing throughout the pandemic on non-traditional platforms to reach swing voters and mobilize younger voters that don’t consume political media throughout the day,” said former Obama press secretary Ben LaBolt. “He has the singular ability to credential how Vice President Biden would approach the job in the Oval Office.”

His appearance on the campaign trail this week fills a gap left by Biden, who has been in Delaware since Monday for meetings and preparation ahead of the second and final presidential debate.

Biden and Trump will face off Thursday in Nashville, Tennessee.

Watch live coverage of the debate at 8 p.m./7 p.m. CT with NewsNation on WGN America, on NewsNationNow.com or download our free app.