Democrats Face Test of Party Unity as They Plan Next Legislative Steps

WASHINGTON—In the first months of President Biden’s term, Democrats on Capitol Hill unified around his $1.9 trillion coronavirus relief proposal, quickly passing through Congress a package that closely resembled Mr. Biden’s original plan and notching an early achievement.

But Mr. Biden and Democrats will face a far more complicated set of political and policy decisions as they seek to move forward with Mr. Biden’s push for an infrastructure and climate package.

Without a looming deadline to quickly mobilize Democrats, the process for passing another major bill could take months, as...