WASHINGTON (AP) — Barack Obama will make his return to the presidential campaign trail Tuesday night with a grassroots fundraiser for Joe Biden. The online fundraiser is expected to raise millions and give the first hint of whether the party’s most popular figure can transfer some of that political mojo to his former running mate. But Obama’s reemergence is not without risks for Biden. It offers President Donald Trump’s campaign an opportunity to resurface some of their favorite attacks on the Obama administration’s policies. And it could reinvigorate progressive concerns about a return to the status quo of the Obama administration.