Joe Biden just won the presidency. That may turn out to be the easy part. The president-elect already was braced to deal with the worst health crisis the nation has seen in more than a century and the economic havoc it has wreaked. Now, he has to build a government while contending with a Senate that could stay in GOP hands, a House sure to feature fewer Democratic allies and a public that includes more than 70 million people who would prefer that President Donald Trump keep the job.