WASHINGTON (CNN) - It's (officially) official: The GOP tax plan would add more than $1 trillion to the federal budget deficit over the next decade --- even when factoring in economic growth.
And this could put some Republicans --- like Sen. Bob Corker --- between a rock and a hard place.
The Tennessee lawmaker has previously pledged that he won't vote for a plan that adds a single penny to the federal debt.
For some time, Republicans made a plausible argument: Government estimates, which projected a cumulative $1.4 trillion added to the debt, didn't take into account a boom of economic growth that the tax package would prompt.
But now, the nonpartisan Joint Committee on Taxation says economic growth will make up for only $408 billion of that, leaving a gaping $1 trillion hole to fill.
"No," Corker said when asked in October if he would back a tax plan that would hike budget deficits. "I mean, I've stated that clearly. ... I want to make sure that it's not something that increases deficits." Corker has already voted to advance the bill on procedural votes.
The news also clashes with the Trump administration's repeated promises that tax reform would pay for itself.
A GOP source told CNN's Phil Mattingly late Thursday that Corker's concern prompted a brief delay during a procedural vote on the bill on the Senate floor. GOP Sens. Jeff Flake of Arizona and Ron Johnson of Wisconsin also briefly delayed their votes.
The source added that the deficit trigger --- a mechanism that could be added to the bill to hike taxes if economic growth was too low --- ran into serious problems. Republicans were working on other possible solutions to address Corker's deficit concerns.
Another big remaining question is whether Americans really care about the deficit anymore. Polling from the Pew Research Center shows concern about the deficit has plummeted more than 20 points since the tea party wave in 2011.
The Senate is still looking to deliver its first landmark piece of legislation under Trump. An attempt to repeal and replace Obama's signature health care law failed dramatically over the summer.