Some frustrated Democrats say strategic blunders by Senate Majority Leader Charles E. Schumer (D-N.Y.) and White House Chief of Staff Ron Klain were, in large part, to blame for Biden failing to win passage of a massive social spending and climate plan. The men too frequently sought to appease progressives and their allied groups while antagonizing the moderates needed to pass the legislation, known as Build Back Better, they say.

After that bill died in December, leaving Democrats reeling, Schumer and Klain doubled down on the same strategy, pivoting to a quixotic showdown over voting rights that further alienated the moderate lawmakers they still need to revive at least part of the spending plan.

The two leaders played “more to public interest groups than the needs of the U.S. Senate,” a Democratic senator said. The senator was one of 20 Democratic lawmakers and administration officials who were interviewed for this story, most speaking on condition of anonymity to candidly discuss what they described as the party’s legislative missteps.