Members on both sides of the aisle are concerned that the provision will create a fair amount of political resistance to the bill.
"There always a chance with tax policy that you're going to get a backlash on one side of the aisle or the other and it could [sink] the extenders package," Sen. Mark Prior (D-Ark.) told The Hill, adding, "But I do trust [tax writers'] judgment to try to put something together that they feel like they could get 60 votes for."
Democratic leaders need at least 1 Republican senator to cross the aisle and support the bill. Sen. Chuck Grassley (R-Iowa), the ranking member on Senate Finance, told The Hill achieving that feat is a tall order because of how the legislation treats carried interest.
"I think it will be difficult," he said.
Grassley has also not been a part of any discussions on the bill.
"They're seeing what they can work out among the Democrats, first, between the Ways and Means Committee and Baucus' staff," he said.
Grassley is withholding judgement on the bill until he sees all its details. Sen. Ron Wyden (D-Ore.) is also taking a wait-and-see approach to the legislation.