President Joe Biden and former presidents Barack Obama and Donald Trump stump for Senate and governor in one of the biggest and closest swing states, Pennsylvania.

President Joe Biden reunited Saturday with his former boss Barack Obama at a Pennsylvania rally to campaign for Democrats and energize midterm voters, just as former President Donald Trump campaigned across the state for Republican candidates at a rally where he hinted at his 2024 ambitions.

Biden took to a Philadelphia stage with Senate candidate John Fetterman and gubernatorial nominee Josh Shapiro. They were joined by Obama, who has leaped into the campaign proxy war in the past few weeks.

“This crowd is so loud, I think they can hear us in Latrobe,” Biden told the cheering supporters at Temple University in a reference to Trump’s speech outside Pittsburgh. “They’re going to hear us on Tuesday.”

Later in the evening in Latrobe, Trump stumped for Mehmet Oz, the celebrity doctor locked in a tight Senate battle with Fetterman, and Doug Mastriano, the state senator running for governor who has trailed far behind Shapiro in public polls amid fundraising struggles and ties to far-right figures.

The intense focus on Pennsylvania comes days before the state could determine which party controls the 50-50 Senate. And the state is set to be a focal point of presidential politics for the next two years, particularly if Biden and Trump face off again. Trump opened his speech by telling his supporters to vote for Oz and Mastriano, but also alluded to his expected run for a second presidential term, saying in a “very, very, very short period of time” supporters would be “so happy.”

“I’d like to do it,” he said, to cheers from the crowd eager for a possible presidential announcement. “But you know what? I really mean this — I want to have the focus tonight be on Dr. Oz and on Doug Mastriano.”

Trump’s rally at a regional airport capped a long day of campaigning by candidates and surrogates across the state. Fetterman and Obama kicked off the day of campaigning in Pittsburgh. The lieutenant governor has the best chance of any Democratic Senate candidate of flipping a seat this election, with GOP Sen. Pat Toomey’s retirement spawning a nasty and expensive race to replace him.

Obama, in a blue button-down shirt, spoke after Fetterman, who had taken to the stage in his trademark black hoodie. The former president addressed the crowd on a range of issues from abortion to gun violence and dinged Republican politicians as lacking any plans to address inflation and rising crime.

“Pennsylvania, you’ve got a choice between politicians who seem willing to say anything and do anything to get power, and people who see and care about you and share your values,” Obama said.

But a once-large Democratic polling lead in the race has narrowed following a barrage of Republican attacks on the issue of crime — and a difficult debate performance by Fetterman, who is recovering from a stroke he suffered this spring.

Speaking in Philadelphia, Biden argued that Fetterman would help the Senate pass a federal ban on assault weapons. He also riled up the crowd by saying that Oz would support a national abortion ban — which he promised to veto if such a bill came to his desk.

Biden’s appearance is notable in part because the Democratic president, whose national approval rating hovers in the low 40s, has largely campaigned in blue states this fall, including Oregon and California, while mostly avoiding the places that he won only narrowly two years ago. But he got the crowd going before Shapiro, Fetterman and Obama spoke to voters in Philadelphia on Saturday.

It was Obama who got the loudest cheers from a relatively young crowd at Temple University, where the White House said about 7,500 supporters packed in although dozens of seats in the upper rafters remained empty.

The former president called Biden an “outstanding” president but pointed to the 2010 and 2014 midterms as an example of what Democrats must avoid, waxing about what might have gone differently had his party kept the majority. He also sought to illuminate the stakes of this year’s midterms, referencing the Jan. 6 attack on the U.S. Capitol and knocking Mastriano and Oz for not acknowledging publicly that Biden legitimately won the 2020 election.

“When true democracy goes away, people get hurt. It has real consequences,” Obama said.

Hours later in Latrobe, Trump repeated his false claims of his own 2020 victories, saying “I believe we won Pennsylvania twice.”

The rally about an hour from Pittsburgh featured both Oz and Mastriano, who each spoke before the former president took the stage and later joined him partway through his roughly two-hour address. The two candidates have seldom appeared together and have taken very different approaches to campaigning in the swing state.

Mastriano has leaned into the party’s base while making few attempts to reach moderate voters. Addressing the crowd alongside Trump Saturday night, his call to end vaccine and mask mandates in schools was met with cheers.

Oz, who has looked to appeal to suburban voters, stuck to more traditional issues when addressing the crowd prior to Trump’s arrival, slamming Democrats over inflation and government spending and branding Fetterman as soft on crime. He joined the former president on stage only briefly, telling the crowd to reach out to 10 people the following day and “tell them that I will bring change to Washington.”

Trump has a lot riding on Republicans’ success in Pennsylvania, particularly after he endorsed Oz in the wide-open GOP primary earlier this year. His super PAC, MAGA Inc., has also spent millions on ads supporting Oz in the past few weeks. He told supporters on Saturday that control of the Senate could come down to the state, saying Oz was “going to make the difference between a country and not a country.”

The former president also hinted at an Iowa rally on Thursday night that he could announce a 2024 presidential run in the coming weeks. Pennsylvania is among the states that would hold special significance in a Biden-Trump rematch as it was the state that put the Democratic president over the 270-vote threshold in the Electoral College two years ago.

A possible 2024 run was a recurring theme in Trump’s speech. At one point, a large screen ran through tweets of poll numbers, including one of a GOP presidential primary poll that showed Trump leading with Florida Gov. Ron DeSantis in second place. The former president referred to his possible rival as “Ron DeSanctimonious.”

A third former president also hit the campaign trail Saturday one state over: Bill Clinton joined New York Gov. Kathy Hochul at a rally in Brooklyn, hoping to give a boost to her closer-than-expected race with Rep. Lee Zeldin. They were joined by Senate Majority Leader Chuck Schumer and New York City Mayor Eric Adams. A day earlier, Vice President Kamala Harris also campaigned for Hochul during a visit to New York City.

“Why is this a close race? Because of inflation. When the cost of living goes up, it’s unsettling for people,” Clinton told the crowd.

“But just take a moment and actually think,” he continued. “The Democrats, led by our governor, are actually doing something to lower costs and to improve public safety.”

Meanwhile, Zeldin was upstate on Saturday, with several campaign stops in the Hudson Valley. He is set to hold an evening rally in Chester with former Rep. Tulsi Gabbard, the one-time Democratic congresswoman-turned Republican surrogate.

Alex Thompson contributed to this report.

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