Democratic presidential candidate called time on Donald Trump’s presidency at a rally in Cedar Rapids on Saturday night.
“We must defeat the most dangerous president in the modern history of this country,” Sanders told around 3,000 supporters packed into the US Cellular Center.
“This is the campaign where the working class of America is going to stand up and say loud and clear: Enough is enough.”
Sanders is the frontrunner in polls heading into the Iowa caucus, the opening salvo in the US primary season.
The veteran left-wing campaigner faces strong challenges from former vice president Joe Biden, Senator Elizabeth Warren and Mayor Pete Buttigieg, among others.