President Donald Trump says that his ballroom project is needed for national security, but should taxpayers foot the bill?It's a question that's splitting Republicans on Capitol Hill after an alleged gunman stormed a security checkpoint at the White House Correspondents' Dinner held at the Washington Hilton on Saturday. The suspect is now being charged with attempting to assassinate the president, among other counts. In response, three Republican senators — Lindsey Graham of South Carolina, Katie Britt of Alabama, and Eric Schmitt of Missouri — announced legislation on Monday to provide $400 million to build a ballroom on the White House grounds. They say the money would pay for construction and security infrastructure underneath the ballroom, including a "Secret Service annex." "I'd like to vote as soon as possible to accelerate what America needs: a secure facility for the president and others to meet in," Graham said. "Private donations can be used, but I think that they should be used for buying china and stuff like that." Graham said on Monday that the White House supports the bill, but it didn't immediately respond on Tuesday when Hearst's Washington News Bureau tried to confirm that. The White House also didn't respond to emailed questions asking if taxpayer money is necessary for the project, given that the president has previously said it would be paid for through private donations. "It's not costing the taxpayers anything," White House press secretary Karoline Leavitt told reporters in October. "The president is privately funding this ballroom addition to White House grounds."Graham said the cost of his bill could be offset using customs fees, but at least some Republicans argue the project should remain privately funded. “We have $39 trillion in debt. Maybe we ought to stop spending money," Sen. Rick Scott, R-Fla., said. Democratic leaders oppose the project altogether. Senate Minority Leader Chuck Schumer, D-N.Y., told reporters on Tuesday that it has nothing to do with national security. "It is not necessary. It's typical of what is wrong with Donald Trump, focusing on the wrong things that appease his ego and don't help the American people one bit," Schumer said. The project, which has already led to the demolition of the White House East Wing, also faces legal barriers. In a social media post after Saturday's attack, Trump said a "ridiculous" lawsuit challenging the project should be dropped immediately. Trump added, "Nothing should be allowed to interfere with its construction, which is on budget and substantially ahead of schedule!!!"But the preservationists who brought the lawsuit aren't backing down. "We have always acknowledged the utility of a larger meeting space at the White House. Building it lawfully requires the approval of Congress, which the Administration could seek at any time," said Carol Quillen, president and CEO of the National Trust for Historic Preservation, in a statement. Acting Attorney General Todd Blanche vowed to continue fighting back in court when asked about next steps on Monday. A federal appeals court has allowed the project to continue for now. Another hearing is set for June 5 to review the case.Even if the president prevails, the ballroom is not expected to be complete until the end of his term. It's also unclear whether an event like the White House Correspondents' Association dinner would be held at the ballroom. It's organized by a private group, not the government, and the turnout for Saturday's event would've far exceeded the expected capacity of the ballroom.