Republican Sen. Mike Rounds said Thursday he's willing to vote for a 22 percent corporate tax rate if that's necessary to win passage of the tax reform bill this week, despite the White House's insistence on 20 percent.

The Wall Street Journal reported late Wednesday that Senate Republicans are considering whether they should set the corporate tax rate above 20 percent — possibly 21 percent or 22 percent — to make room for other items in the bill. The current rate stands at 35 percent.

Republicans hold 52 seats in the 100-member Senate, so the administration cannot afford to lose more than two GOP votes since Democrats are united in their opposition to the proposal.

"The key is to get to 50 plus one [votes]," said Rounds, who met with President Donald Trump earlier this week to discuss the tax bill. "If we can get 52 in and bring this through the finish line at 52, that's what this is all about. It's the bottom line."

When asked on CNBC's "Squawk Box" whether he'd be fine with a 22 percent corporate rate among other changes, the South Dakota Republican said: "If that's what it takes to keep the whole team together, then that's what we'll end up at."

"The last discussions we've had have all been based upon the 20 percent rate," he added.

GOP Sen. Lindsey Graham said a 22 percent rate "doesn't make this a horrible bill," according to the Journal.

Trump has pushed to keep the corporate rate at 20 percent, and the administration has previously said there is "no room to negotiate." The lower rate is seen by the administration as more attractive for U.S. businesses to invest at home.

In September, top White House economic advisor Gary Cohn said "We are at 20. Twenty is a bright-line test for us. The president said it. He said it ... and he's been very clear about it."