House lawmakers slap down Trump's veto of $740 billion defense bill, now heads to Senate for final showdown

• House lawmakers voted 322-87 to override President Donald Trump's veto of a must-pass bill to fund the US military.
• The override now heads to the US Senate.
• The veto override would be the first such act during Trump's presidency, if it passes in the Senate.

House lawmakers overwhelmingly voted to override President Donald Trump's veto of a must-pass bill to fund the US military, setting up the scene for the first potential override by both chambers during his White House tenure.

US Representatives on Monday evening voted 322-87 to override Trump's veto of the National Defense Authorization Act (NDAA), which allocates around $740 billion earmarked to fund the US military for the next fiscal year. The bill includes substantive changes in troops deployments overseas, a 3% pay increase for service members, as well as renaming military bases that honor Confederate leaders within the next three years.

The bill was passed with strong bipartisan support in a 335-78 House vote earlier in December, which exceeded the two-thirds majority needed to strike down Trump's veto. The US Senate then passed the bill in a 84-13 vote, a group that included the president's fervent allies like Majority Leader Mitch McConnell and Republican Sen. Lindsey Graham of South Carolina.

"Today, the House reiterated - in a resounding, bipartisan way - that our service members and national security are more important than politics," Democratic Rep. Adam Smith of Washington, the chairman of the House Armed Services Committee, said in a statement after the vote.

"By overriding the President's veto, the House prioritized compromise and sound policy over legislative nihilism and blind political loyalty," Smith added. " By overriding the President's veto, the House asserted the role of the legislative branch and underscored the importance of our constitutional separation of powers."

Prior to the override vote, Republican Rep. Mac Thornberry of Texas, the ranking member of the House Armed Services Committee, told his colleagues to vote "on what is actually in the bill rather than distortions or misrepresentations."

"Your decision should be based upon the oath we all took, which was to the Constitution rather than any person or organization," Thornberry said in a note that was obtained by POLITICO.

Thornberry, who is not running for reelection, reportedly did not include Trump's name in the note and did not specifically advise his colleagues to vote in favor of an override.

Trump vetoed the bill on December 23, saying the reason for his disapproval was because it threatened national security.

"Unfortunately, the Act fails to include critical national security measures, includes provisions that fail to respect our veterans and our military's history, and contradicts efforts by my Administration to put America first in our national security and foreign policy actions," Trump said in a statement. "It is a 'gift' to China and Russia."

Trump additionally took aim at the provision to rename US military bases and streets honoring Confederate leaders, which includes at least 10 US Army installations throughout the country.

"Over the course of United States history, these locations have taken on significance to the American story and those who have helped write it that far transcends their namesakes," Trump added in his statement. "My Administration respects the legacy of the millions of American servicemen and women who have served with honor at these military bases, and who, from these locations, have fought, bled, and died for their country."