US election: Democratic White House race kicks off as Iowa caucuses open

Americans on Monday kicked off the first vote of the 2020 presidential race as the state of Iowa opened its caucuses, the first step in determining which Democrat faces incumbent Donald Trump in November.

Just 41 Iowa delegates are up for grabs, a fraction of the 1,991 needed to secure the Democratic nomination, but the vote is a critical early look at the viability of the 11 candidates still in the race and who will carry momentum forward.

Far-left Senator Bernie Sanders and moderate former vice president Joe Biden are the frontrunners. But polling has fluctuated and Iowa's quirky caucus system -- where voting is by public declaration for a candidate and not by secret ballot -- can make the night hard to predict.