The legislation will now go to the GOP-controlled Senate. Despite Senate Majority Leader Mitch McConnell's support for Trump's action, he will have to take up the privileged resolution to block it. It could very well get through the Senate: only four Republicans need to join 47 Democrats in backing it for it to garner the simple majority needed to pass.
Still, Trump plans to veto the bill. Democrats would then have a much tougher time convincing two thirds of both chambers — or 290 and 67 lawmakers in the House and Senate, respectively — to override the president. Last week, Trump told reporters that he does not "think it survives the veto" as "we have too many people that want border security."
Even if Congress fails to block the emergency declaration, it will likely reproach his flex of executive power in a way rarely seen during his more than two years in office. It already dealt him a blow on immigration — his signature issue — by giving him only about $1.4 billion of the $5.7 billion he sought for border barriers in the funding law signed earlier this month.
In addition, numerous U.S. states and several independent groups have already filed lawsuits challenging the emergency declaration. Trump believes the Supreme Court will ultimately rule in his favor.
The White House aims to secure $8 billion to build border barriers by circumventing Congress. He will use the emergency declaration to draw $3.6 billion from the Department of Defense's military construction funds. With other executive actions, he plans to divert $2.5 billion from the Pentagon's drug interdiction program and $600 million from the Treasury Department's drug forfeiture fund.
On Monday, House Speaker Nancy Pelosi contended Trump's "power grab usurps" the power of the purse given to Congress in the Constitution.
"We would be delinquent in our duties if we did not resist, if we did not fight back to overturn the President's declaration," the California Democrat said. "To not do that would be to abandon our own responsibilities. We do not intend to do that."
On Tuesday, McConnell said he "couldn't handicap" how a vote would go in the Senate. The Kentucky Republican expects the chamber to vote before its next recess on March 18. He noted that GOP senators had a "fulsome" discussion about the emergency declaration during a lunch Tuesday, which Vice President Mike Pence attended.
At least three Senate Republicans — Sens. Susan Collins of Maine, Lisa Murkowski of Alaska and Thom Tillis of North Carolina — have signaled they will support the legislation to block the emergency declaration. Both Collins and Tillis face re-election bids next year in ideologically split states.
GOP lawmakers will have to balance a desire to back Trump and the Republican voters who overwhelmingly support him with a professed opposition to expansions of executive power.
"As a U.S. senator, I cannot justify providing the executive with more ways to bypass Congress. As a conservative, I cannot endorse a precedent that I know future left-wing presidents will exploit to advance radical policies that will erode economic and individual freedoms," Tillis wrote in a Washington Post column announcing that he would vote to disapprove of the emergency declaration.
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