 U.S. President Joe Biden is on his way to Pennsylvania to mark the Martin Luther King Jr. holiday Biden plans to spend the Monday holiday volunteering at Phil Abundance, a hunger relief organization in Philadelphia. Meanwhile, Biden's Republican rivals are in Iowa for the first in the nation Iowa caucuses, former President Donald Trump and his top primary rivals, including former U.S. ambassador to the United Nations Nikki Haley and Florida Governor Ron DeSantis are asking would-be caucusgoers to brace frigid temperatures and turnout to caucus.