KEY POINTS
  • A national emergency declaration by President Donald Trump over border security could wind up hurting Republicans, Sen. Marco Rubio says.
  • Asked whether he supports Trump's position, which includes the wall, Rubio says, "Anything that makes the border more secure, I'll be in favor of supporting."

A national emergency declaration by President Donald Trump over border security could wind up hurting Republicans, GOP Sen. Marco Rubio told CNBC on Wednesday.

The Florida Republican contended that Trump was elected on the promise of building a wall along the U.S.-Mexico border and the president has to "keep that promise." But "we have to be careful about endorsing broad uses of executive power," he added. "I'm not prepared to endorse that right now."