And it would drive up the cost of the bill in ways that could make Democrats cringe. The Gang of Eight bill as written would spend over $6 billion in securing the border. The new amendment's "border surge" could drive up the cost of the legislation by another $30 billion, according to The Washington Post.
Even Corker, a co-author of the compromise, suggested that it overcompensates on border security simply to secure Republican votes.
"For people who are concerned about border security, once they see what is in this bill, it's almost overkill," the senator said on MSNBC.
Will The House Buy It?
The border compromise could be a crucial turning point for the bill in the Senate. But what about the House?
The House Republican rank-and-file has a low appetite for immigration reform that contains a pathway to citizenship, like the Senate bill does.
Leadership so far has stood with the backbenchers. Speaker John Boehner (R-Ohio) and other GOP leaders have declared the Senate bill dead on arrival in the House. And this week, Boehner affirmed that he will not bring a bill to the floor without the majority support of his conference.
On Thursday, Boehner refused to comment on the Senate border deal.
"Regardless of what the Senate does, the House is going to work its will," he said at a press conference.
Meanwhile, a House committee recently passed a tough enforcement-only bill that shows GOP concerns go beyond just border security. The proposal would make it a federal crime to be present in the U.S. without legal documents and it would repeal the deferred action program that grants deportation relief to some undocumented young people.
This week's Congressional Budget Office report that showed the Senate bill would reduce the federal budget deficit wasn't enough to convince skeptical House Republicans to change their tune. And it's not clear that a Senate bill with overwhelming bipartisan support will be enough to spark the House to act either.
"I don't know, Mother always told me that if 70 people jump off a cliff, you shouldn't follow them," Rep. Tom McClintock (R-Calif.) told Politico on Wednesday. ABC News' Jeff Zeleny and Jim Avila contributed reporting.