On infrastructure — so high in its potential for bipartisanship that it has become a Washington cliche — Senate Democrats are already confronting an internal dispute over whether to use a party-line procedural tool that would allow them to pass a bill with no GOP support. Biden’s comprehensive immigration overhaul — a “Day One” priority for the president — is also struggling to gain traction even in the House, as Democratic leaders begin an uphill battle to count votes in favor of a sweeping bill…

House Democratic leaders have privately started to gauge the level of support for the president’s plan — formally called the U.S. Citizenship Act — and found that, at this point, it would struggle to pass, according to people familiar with the matter.

Scores of new lawmakers haven’t tackled immigration previously and know little about the issue. Many lawmakers also feel that such a massive overhaul is moving too quickly in the House, while moderates fear supporting controversial legislation that has no real path in the Senate, said the people, who spoke on the condition of anonymity to discuss private Democratic caucus dynamics.

Some moderates had indicated that they would oppose Biden’s immigration legislation if it were fast-tracked to the floor for a vote primarily on process objections rather than on its substantive merits, these people said. White House officials have conducted at least one staff-level briefing for Congress on Biden’s plan, but there has been little administration engagement otherwise so far, according to aides and lawmakers.