Democratic presidential hopeful Amy Klobuchar stressed the need for another presidential debate before the Iowa caucuses, even if it coincides with the president's impeachment trial in the Senate.

"I have made it very clear that there should be no excuses," Klobuchar, a senator from Minnesota, said Sunday on "Face the Nation." "I'm ready to debate at midnight if that's what we have to do. We have to have a debate before the Iowa caucuses."

The next Democratic presidential debate is scheduled for January 14 in Des Moines and would be the final debate before the Iowa caucuses on February 3. But that could end up occurring right in the middle of the Senate's impeachment trial, though the details of the proceedings remain unclear.

House Speaker Nancy Pelosi hasn't yet transmitted the two articles of impeachment against President Trump, which were adopted Wednesday, to the Senate. The upper chamber, however, has blocked off the full month of January for the proceedings.

Klobuchar is one of five Democratic senators still in the presidential race, and the Senate trial would take them away from the campaign trail in the run-up to the Iowa caucuses. Senate rules require senators attend trial proceedings six days a week until a final judgment is reached.

But Klobuchar said it's her "first belief" that Democrats "have to have the debate" before Iowans go to the caucuses, and said the next debate may have to take place in between trial proceedings, ensuring Democratic senators running for president could participate.

Klobuchar said she will lean on surrogates to make the case for why she should take on Mr. Trump in November while she's participating in the trial.

"We are going to have so many people showing up to help me if I'm doing my constitutional duty, which comes first, as a U.S. senator," she said. "I'll have to Skype in for town hall meetings. There is modern technology. I think we're going to find a way to do this."

Klobuchar and six other Democrats were on the debate stage in Los Angeles on Thursday, and the following day she was back in Iowa for a bus tour and full days of events, the senator said.

"I don't need a lot of sleep. I work really hard," she said.

Pelosi said last week she wouldn't name impeachment managers, who will effectively serve as prosecutors arguing the case against the president, until Senate Majority Leader Mitch McConnell unveils the procedures for the trial. McConnell and Democratic Minority Leader Chuck Schumer have yet to reach a deal on the structure of the impeachment trial.

Lawmakers left Washington, D.C., last week for the two-week holiday break and won't return until the new year.