Republican members of the Senate Finance Committee projected optimism on Monday after meeting with President Trump about the future of tax reform legislation, which could pass the Senate this week.

"There is growing momentum for this, and I'm confident that we're going to get this done soon," Sen. Pat Toomey, R-Pa., told reporters outside the White House on Monday after a closed-door lunch with lawmakers, Trump and Vice President Mike Pence.

Sen. John Cornyn, R-Texas, said the Senate plans to take up its version of tax legislation this week as Republicans race to meet a self-imposed deadline to put a bill on the president's desk by the end of the year. Cornyn said he believes the upper chamber's plan makes "improvements" over tax legislation passed by the House earlier this month.

Sen. Orrin Hatch, who chairs the Senate Finance committee, said he expects Republicans from both the House and Senate will resolve their differences in conference once both chambers have passed their bills.

"We're generally able to get together and solve these problems, and I think we will," Hatch said.

Several GOP senators have yet to back the tax bill, however, and Senate leaders have not said whether their plan has enough support to pass.

But Hatch suggested Monday that Republicans believe they will find a way to persuade reluctant members to vote for the legislation.

"We intend to get to 50," the Utah Republican said.

Pressed on whether Sen. Ron Johnson, R-Wis., could derail the passage of tax reform by remaining opposed to the bill, Hatch declined to single him out as a problem.

"We always have to deal with anybody, so it's not one particular person," Hatch said.

Trump has pushed lawmakers to pass tax reform by the end of the year and has advocated for Republicans to repeal Obamacare's individual mandate in the process. The House GOP bill does not repeal the mandate, which requires most people to purchase health insurance or pay a penalty. However, the White House has not described the healthcare provision as a must-have in the bill Trump hopes to sign next month.

Asked whether congressional Republicans will advance tax reform legislation before Christmas, Hatch remained optimistic.

"I hope so," he said.