White House Deputy Press Secretary Hogan Gidley said a vote against President Trump's national emergency declaration is a vote against the interests of the American people.

Gidley made the remark on "America's Newsroom" Thursday, just hours before the Senate will vote on a resolution to block the declaration.

Due to the small Republican majority in the upper chamber -- 53-47-- it takes only four Republicans to vote in favor of the bill to block the declaration.

The declaration was an effort by Trump to steer an extra $3.6 billion to build the border wall. If the move is blocked, Trump would likely use his first veto since taking office.

"If they oppose the president, then they stand in opposition to the American people, to American communities, and to safety and security, because that's what this measure does," Gidley said.

He argued that Congress has had decades to address border security and immigration reform, but they have failed to do so. He said Trump is well within his constitutional rights to use executive power to address the crisis at the border.

"This vote today draws a clear line in the sand of which party and which president actually stands for the American people, and those who stand for those who are here illegally and unlawfully," Gidley said.

"[Democrats] are now the party of open borders. And they have to own that."

Watch the "America's Newsroom" interview above.

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