Republican Sen. Lindsey Graham led the charge of lawmakers Sunday sounding off on President Donald Trump's decision to declare a national emergency.

Graham doubled down on his support for the move, insisting there was an emergency at the southern border that necessitated using military funds before slated projects including housing for military families and the construction of a middle school.

Some Republican lawmakers expressed softer support and apprehension, while congressional Democrats flatly denied the move, calling it an abuse of power.

Trump admitted Friday that the declaration is widely expected to face a string of legal troubles amid growing questions about its validity.

Republican Sen. Lindsey Graham doubled down on his support for President Donald Trump's declaration of a national emergency in an interview with CBS' "Face the Nation" that was aired Sunday.

When host Margaret Brennan brought up projects that are currently slated to be built using military construction spending, including housing for military families and a middle school in Kentucky, the South Carolina senator stood behind his support for funding projects at the border.

Despite the possibility that the funding would be diverted away from those projects for Trump's border wall, Graham said the national emergency was the right move.

"Let's just say for a moment that he took some money out of the military construction budget," Graham said. "I would say it's better for the middle school kids in Kentucky to have a secure border. We'll get them the school they need. But right now we've got a national emergency on our hands."

—Face The Nation (@FaceTheNation) February 17, 2019

Widespread concerns among lawmakers

After the declaration Friday, lawmakers on both sides of the aisle cast the move as an unprecedented maneuver around Congress to take control of military funding.

Read more: IT'S OFFICIAL: Trump declares national emergency to build his border wall

On Sunday, other lawmakers didn't express as firm support for the situation as Graham did.

Republican Sen. Ron Johnson said on NBC's "Meet the Press" that "many of us are concerned about" the declaration.

Though the declaration is similar to "the expansion of authority Congress has given past presidents," Johnson said he wished "he wouldn't use it in this case. But again, I understand his frustration."

The chairman of the Senate Homeland Security and Governmental Affairs Committee said he would take a "careful look" at how the funding battle plays out and Trump's plan for the money.

"I'm going to take a look at the case the president makes," Johnson said. "And I'm also going to take a look at how quickly this money is actually going to be spent versus what he's going to use.

As for his opinion on if there is an actual emergency at the southern border, Johnson said: "again, I'm going to take a look at it and I'll, you know, I'll decide when I actually have to vote on it."

—Meet the Press (@MeetThePress) February 16, 2019

Republican Rep. Will Hurd of Texas flatly denied the move, calling it inappropriate, saying on CBS' "Face the Nation" that it "is not a tool that the president needs in order to solve this problem."

Democratic lawmakers issued harsher hits against the declaration, with Illinois Sen. Tammy Duckworth suggesting Congress take legal action against Trump if he follows through with this "type of executive overreach."

"Frankly, the president is trying to take the power of the purse away from the legislative branch," she said. "We are co-equal branches of government and he is trying to do a type of executive overreach, and it's just really uncalled for."

Democratic Sen. Sherrod Brown told CNN's "State of the Union" that the declaration violated the Constitution and was a first of its kind of emergency where a president invoked such authority after his other demands fell through.

"He couldn't get the Mexicans to build the wall, he couldn't get Congress to vote the money in," Brown said.

"That's why you see so many Republicans saying don't do this," Brown said. "Republicans are afraid that he's going to take the money from somewhere else and something they care about, but, fundamentally, they think it's a president who failed, who hates to lose, who is acting childish."