U.S. Sen. Susan Collins, R-Maine, is flanked by Coast Guard Capt. Brian LeFebvre, left, and Rear Adm. Andrew Tiongson, right, as she addresses reporters after the ribbon-cutting at a U.S. Coast Guard regional command center Wednesday in South Portland. Collins said that she would vote for a congressional resolution disapproving of President Donald Trump's emergency declaration to build a wall on the southern border. She is the first Republican senator to publicly express support for such a resolution. Credit: David Sharp | AP

Numerous Republicans in the U.S. Senate rightfully expressed constitutional concerns when President Donald Trump announced his emergency declaration to bypass Congress and dedicate roughly $8 billion to construct more barriers on the southern border.

Among the concerned voices on the right, Maine’s Susan Collins was the first senator to support the idea of a resolution to terminate the declaration. And she’s still largely alone to start the week, though fellow moderate Lisa Murkowski has said she’s “likely” to support the resolution as well.

The Democratic-led resolution to block Trump’s action is slated for a vote in the House of Representatives Tuesday and is an option Congress afforded itself under the the National Emergencies Act of 1976 — the same law that the president is using to make his declaration.

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The resolution will likely pass the Democrat-controlled House, but faces a much more uncertain future in the Republican-led Senate. Collins was the only Republican senator to voice support for such a resolution last week. As of Monday morning, only one House Republican, Rep. Justin Amash of Michigan, had signed on as co-sponsor.

“The same congressional Republicans who joined me in blasting Pres. Obama’s executive overreach now cry out for a king to usurp legislative powers,” Amash tweeted last week. “If your faithfulness to the Constitution depends on which party controls the White House, then you are not faithful to it.”

Amash provides a refreshing example of ideological consistency winning out over party loyalty, and hopefully other Republicans concerned about the trend of ceding power to the executive branch will follow suit.

Even if enough other emergency declaration-skeptical Senate Republicans join with Collins and Amash in rightly voting to terminate the emergency declaration, it looks highly unlikely that there will be enough votes to overturn a guaranteed Trump veto should the resolution even make it to his desk.

This is a fight, therefore, that will almost surely be decided in court. While Collins has accurately framed Trump’s declaration as having “dubious constitutionality,” the president’s prediction that the Supreme Court will eventually uphold his move, as it did with his travel ban, could eventually and disappointingly prove correct.

Though the path forward for the termination resolution is decidedly uphill, it’s still a fight worth having in the sense that Congress needs to reassert its status as a co-equal branch of government.

[Opinion: Congress has let presidents do its job. Now Trump has taken advantage of that.]

“Whether or not it should be legal is a different matter. Congress has been ceding far too much power to the executive branch for decades,” Sen.Mike Lee, R-Utah, said about the emergency declaration. “We should use this moment as an opportunity to start taking that power back.”

If nothing else, the president’s border wall emergency declaration should be an eye-opening experience for members of both parties that emphasizes overly broad scope and use of the National Emergencies Act. Some Democrats have already suggested using the law to address liberal priorities such as climate change, and that would be an unfortunate escalation that should be avoided.

A better — but admittedly unlikely — way forward here is for Congress to reject Trump’s emergency declaration, work in a bipartisan fashion to revisit the extent it has empowered the presidency through the National Emergencies Act, and come together to have a realistic and re-energized conversation about significant immigration reform that includes both protections for immigrants already living in the U.S., and yes, increased funding for wall infrastructure on the southern border.