evidence: WASHINGTON — President Joe Biden announced Sunday that he will end his presidential re-election campaign, bringing an abrupt and humbling conclusion to his half-century-long political career and scrambling the race for the White House less than four months before Election Day. [...] In a fundraising email, Trump’s campaign said that Biden "quit the race in complete disgrace." Biden’s decision to exit the race less than a month before his party’s convention and a few months before voters head to the polls is unprecedented in the modern political era. The last sitting president to abandon a re-election bid was Lyndon Johnson, whose expansion of the Vietnam War in the 1960s split the Democratic Party. But Johnson’s announcement came in March 1968 — eight months before that election.