PHILADELPHIA (AP) — President Joe Biden struck an economic populist message during the first rally of his reelection campaign. The president told an exuberant crowd of union members in Philadelphia that his policies had created jobs and lifted the middle class. Now, he said, is the time for the wealthy to “pay their fair share” in taxes. His choice of Philadelphia and Pennsylvania – and a friendly union audience — for the campaign venue reflects their crucial role in his reelection effort. The city was the site of his campaign headquarters in 2020 and the state was one of a handful that had voted for Republican Donald Trump in 2016 but flipped back to Democrats four years later.