This week on "Face the Nation," Margaret Brennan speaks with Nikki Haley, the last Republican candidate standing against former President Donald Trump. Plus, Sen. Chris Murphy, one of the key negotiators of the short-lived bipartisan border bill, joins ahead of Sunday's planned vote. Guests: 2024 Republican presidential hopeful Nikki Haley, former U.S. ambassador to the U.N., Former White House counsel Bob Bauer, President Biden's personal attorney, Sen. Chris Murphy, Democrat of Connecticut, CIA deputy director and CBS News senior national security contributor Michael Morell and Samantha Vinograd, former top counterterrorism official at the Department of Homeland Security, CBS News election law contributor David Becker, the founder of the Center for Election Innovation and Research, James Brown, host of NFL Today and CBS News special correspondent