The tightening race in Iowa for the Democratic presidential nomination was on full display Monday night during a forum for candidates in Des Moines.
Bernie Sanders said he'd noticed Hillary Clinton's campaign stepping up its attacks on him.
"The inevitable candidate for the Democratic nomination may not be so inevitable today," the U.S. senator from Vermont said during the Iowa Brown and Black Forum, an event dedicated to minority issues.
The Iowa caucuses are on Feb. 1, and a new NBC/Wall Street Journal poll showed Clinton and Sanders in a statistical tie, since her lead of 3 percentage points was within the margin of error.
During previous campaign stops, Clinton had accused Sanders of being soft on guns and fiscally irresponsible when proposing new government programs.
She's also urged voters to consider a candidate's "electability." The implication was clear: The country may not be ready for a democratic socialist, which is how Sanders describes himself.
Asked during the forum whether she thinks Sanders is unelectable, she said, "Anybody can win. Who would have thought Donald Trump would be leading in national polls?"
Sanders said he respected Clinton but that she was an "establishment politician," and "it's too late for establishment politics."
Topics like immigration and criminal justice dominated the event, which was first held in 1976.
While her rivals had already called for an end to federal deportation raids, Clinton stepped up her criticisms at the event, calling the raids "divisive" and saying they should be stopped.
Martin O'Malley, the former Maryland governor who has trailed in the polls, said the Democratic National Committee has made it more difficult for him to compete by limiting the number of debates.
He also said he's been more progressive than his opponents.
Instead of standing to the political left or right of his rivals, O'Malley said, "I'm to the forward of them."
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