Top Senate Dem "frustrated and disappointed" by Manchin

• "I can tell you the level of emotion at our caucus about the child tax credit is very high," Durbin said. "We were so proud of what we've accomplished there and for this to come up as an issue toward the end was stunning."

Driving the new: Manchin said Wednesday that he is interested in including a 10-year extension of the child tax credit instead of for just one year, which would ultimately increase the cost of the bill.

• However, the senator is seeking to keep the overall cost of the legislation under $1.75 trillion. A 10-year extension would cost more than $1.5 trillion alone, according to a Congressional Budget Office forecast.

The child tax credit is viewed in the Democratic caucus as an effective tool to cut child poverty in half, Axios' Hans Nichols reports.

• The American Rescue Plan passed earlier this year expanded the child tax credit from $2,000 per child to $3,000 per child, but the expansion is due to expire this month.

Go deeper: Manchin seeks child tax credit "we can afford"