When U.S. Sen. Bernie Sanders was planning for the final stretch of the Iowa caucus race, he hoped to be hopscotching the state to hold as many town halls and rallies as possible.

"That schedule is now in the garbage bin," Sanders said in a phone interview with the Des Moines Register shortly before heading into the U.S. Senate chambers Friday for day four of President Donald Trump's impeachment trial.

He and Sens. Amy Klobuchar and Elizabeth Warren — who also happen to be three of the top 5 polling candidates in Iowa — are sitting as jurors in the impeachment trial of President Donald Trump. The trial started soon after the Des Moines Register/CNN/Mediacom poll showed Sanders leading the race for the first time.

The Vermont senator said he still aims to get to Iowa as much as he can in the final 10 days before the caucus, but without shirking his Constitutional duty as a senator.

"I wish very much I could be in Iowa," Sanders said. "I'm not going to tell you this is easy for me, nor, I think for other senators."

On Monday, at his last public appearance in Iowa before heading back to Washington, Sanders implored his supporters to "carry the ball" in the final dash. It was a message he echoed Friday before a series of planned events in the state. He said his campaign's organizing give him "a really good chance to win," by expanding the electorate in the caucus and general election.

"We're going to depend on our surrogates and our volunteers," he said. "... the message of our campaign is 'us, not me.' This is a moment where we'll see if that works, because it will be the 'us,' it will be the grassroots activism, that carries us over the finish line because I won't be able to be in Iowa as often as I hoped to be."

Sanders has had surrogates fanning out all over Iowa, including Oscar-winning filmmaker Michael Moore and U.S. Rep. Alexandria Ocasio-Cortez, who are slated to host a rally in Iowa City on Friday night and other events Saturday before Sanders' aimed return to Iowa.

Sanders said the mood in Washington, D.C., is a stark contrast to that campaigning in Iowa.

"It is two very different worlds," Sanders said. "Obviously, in the Senate right now, this is a very somber moment. It is a very painful and difficult moment. It's not something anybody wanted. But I think when you have a president who is corrupt, I think this had to happen.

"... The process here, of sitting here and listening to the evidence for eight or nine hours a day is a very, very different experience than holding town meetings and rallies in Iowa. I'm going to hope very much I can incorporate both into my mind and do the best that I can in both regards."

Nick Coltrain is a politics and data reporter for the Register. Reach him at ncoltrain@registermedia.com or at 515-284-8361. Your subscription makes work like this possible. Subscribe today at DesMoinesRegister.com/Deal.