The 2020 Iowa caucuses present unprecedented challenges for some top Democratic contenders. Several candidates polling highest in Iowa have been unable to physically spend much time in the state in the final weeks before the vote. Senators Bernie Sanders, Elizabeth Warren, Amy Klobuchar and Michael Bennet have been back in Washington serving as jurors in the Senate impeachment trial of President Trump.

Having a presence in those final weeks in Iowa can be the key to wooing any remaining undecided voters. And this year, there are quite a few.

What’s more, at least one candidate won’t even appear on the ballot in Iowa. Businessman Michael Bloomberg is opting out of the first four primaries and caucuses, making his entry on Super Tuesday ballots.

So, given these new complicating factors, does Iowa matter in a different way than in past elections? How important is this state to the final outcome of the primary? How might the Senators’ scaled-down presence in Iowa the final weeks before the caucuses, affect the results? And really, how much does winning Iowa matter for who eventually earns the nomination .. and the presidency?

To answer that question, we set out to learn from the past. Iowa elections expert Cary Covington and campaign reporter Holly Bailey lay out the complex landscape as we head toward the first state’s vote.

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