WASHINGTON (AP) — President Joe Biden is beginning his Labor Day celebrations with a trip to one battleground state, Wisconsin, before making his third trip in less than a week to another, Pennsylvania. The White House says Biden will be celebrating “the dignity of American workers.” The unofficial start of fall, Labor Day also traditionally kicks off political crunch time, with campaigns scrambling to excite voters ahead of Election Day on Nov. 8. Biden’s trips on Monday will see him return to a theme that was a centerpiece of his 2020 campaign — that labor unions burnished a middle class that built and strengthened modern American society.