Iowa caucuses underway, kicking off 2020 U.S. presidential primary

Democratic presidential candidate Joe Biden, former U.S. vice president, attends a caucus night rally with his wife Jill Biden at Drake University in Des Moines, Iowa, the United States, Feb. 3, 2020. Iowa, a state in the Midwestern United States, is holding Democratic and Republican caucuses Monday night, kicking off the 2020 U.S. presidential primary. (Photo by Joel Lerner/Xinhua)