Manchin tanks Democrats' hopes of passing Biden's big bill by Christmas with last-minute demands to cut the child tax credit

• Manchin has all but sunk the Democratic aim of approving Biden's economic agenda by year-end.
• He raised last-minute concerns about the 10-year cost of a program giving checks to families.

Sen. Joe Manchin of West Virginia all but sank the Democratic goal of approving the centerpiece of President Joe Biden's agenda by Christmas, pushing last-minute changes to the child tax credit and the structure of the cash benefit.

Manchin has been locked in negotiations with Biden on his $2 trillion social- and climate-spending bill. A key part of the legislation is a one-year extension of the child tax credit, which provides families with up to $300 per kid a month. It's scheduled to expire at the end of the year, and the IRS issued final payments to 35 million families on Wednesday.

CNN's Manu Raju reported that the West Virginia Democrat backed slashing the benefit from the legislation entirely. But Manchin later denounced the reports as "bullshit."

"Sen. Manchin is not telling President Biden what to include or not include. He has always been supportive of the child tax credit," a person familiar with his thinking told Insider. "He has also made it clear the cost should not be greater than $1.75 trillion." Over 10 years, the credit would cost about $1.4 trillion, the person added.

All 50 members of the Senate's Democratic caucus, including Manchin, must stay united to approve the bill in the evenly divided chamber. Without Manchin's vote, Senate Democrats can't move ahead and sidestep Republican opposition to approve the sprawling measure.

Some Democratic senators who shepherded the provision said they felt blindsided by Manchin.

"I'm very, very surprised because I thought that there was an agreement on this," Sen. Michael Bennet, an architect of the program, told Insider.

Sen. Ron Wyden of Oregon, the chair of the Senate Finance Committee, later said he'd been contacted by several Democratic senators about drafting a last-minute extension to continue the program into next year.

Those lawmakers "have asked about the possibility of going forward with a separate fix, just on the child tax credit if Build Back Better is put off until the beginning of January," he told Insider.

That group includes Bennet, a Senate Democratic aide familiar with the dynamics said.

For that measure to succeed, it would require 10 Republicans in the Senate to lend their support to avert a filibuster. It didn't appear likely that many Senate Republicans would join Democrats, though some kept the door open depending on the finer details.

"I think that's a much superior way of giving it," Sen. Bill Cassidy of Louisiana told Insider about monthly checks to families. But he added that he wanted to see more details from Democrats, such as payment amount, before making up his mind.

"I think there may be some preliminary conversations in that vein, and we'll see how they unfold," Sen. Lisa Murkowski of Alaska told Insider.

Other Democrats are skeptical about the prospect of Senate Republicans joining Democrats to extend the benefit.

"I wouldn't hold my breath," Sen. Bernie Sanders said.