U.S. Democrats are racing to hammer out the details on two massive pieces of domestic legislation championed by President Joe Biden.On Tuesday, Democratic Senator Joe Manchin of West Virginia said he believed one of the two bills - a $1 trillion bipartisan infrastructure package that cleared the Senate over the summer - might be passed by the House of Representatives this week."If we get that one piece of legislation passed, it shows that in a bipartisan way, we can do something."Manchin commands a key vote that could make or break part of the Biden agenda.In the evenly-divided Senate, Republicans are unified against the Democratic efforts to pass a second spending bill, aimed at expanding social services and tackling climate change.And both Manchin and fellow moderate Democratic Senator Kyrsten Sinema of Arizona are digging in their heels over Biden's plans for a large bill to be passed through what's called reconciliation.Manchin and Sinema have balked at both the size and the scope.And the West Virginia Democrat held firm on how much he thinks the measure ought to cost: $1.5 trillion."I think one-point-five is more than fair."Progressive Democratic lawmakers at one point sought $3.5 trillion to expand prescription drug benefits, offer free community college, and pay coal- and gas-burning energy plants to switch to clean energy.Manchin, who represents a coal-mining state, pushed back on the clean-energy measure and other aspects that have since been cut from the draft.That's caused consternation among House Democrats and piled pressure on Joe Biden and House Speaker Nancy Pelosi to hammer out a compromise.The president met with Manchin over the weekend."It went well. They have a few more things to work out but it went well."Biden told reporters on Monday he hoped to see results by the end of the week."By the grace of God and the goodwill of neighbors."On Tuesday one Democratic lawmaker said Speaker Pelosi told her caucus negotiators have completed work on 90 percent of the reconciliation bill at the heart of Biden's agenda.