Iowa’s U.S. senators, both Republicans, voted against the constitutionality of moving forward with a senate impeachment trial for former President Donald Trump on Tuesday, similar to a vote held in January when Republicans expressed concerns.

The Senate voted mostly along party lines, 56-44, to affirm that the trial was in fact constitutional and could move forward. Six Republicans broke ranks, signaling that a two-thirds majority to convict Trump for inciting an insurrection may be out of reach.

Republicans, including U.S. Sens. Chuck Grassley and Joni Ernst, R-Iowa, say the trial is unconstitutional because Trump already left office. Democrats argue that there is no “January exception” for presidents to abuse their power in their final weeks of office. 

On Jan. 6, a mob of Trump supporters stormed the U.S. Capitol in an effort to stop Congress from counting Electoral College votes. This resulted in five deaths, and Trump has been accused of inciting the violence in a speech he gave before the rioters made their way to Capitol Hill. The House voted to impeach Trump on Jan. 13, one week after the riot.

Now, Trump faces a potential conviction in the Senate which would bar him from running for federal office.

The trial began Tuesday with opening remarks from House impeachment managers and Trump’s legal defense team. Lead House impeachment manager Rep. Jamie Raskin, D-Maryland, gave an emotional speech following a 13 minute video of the events leading up to when a violent mob breached the Capitol.

David Schoen, one of Trump’s defense attorneys, said Democrats are trying to further their political agenda with the trial and create a chilling effect with the video. 

Ernst told reporters on Jan. 26 that while Trump showed poor leadership, she does not think that’s grounds for impeachment. 

“Certainly I believe that he should have been out sooner telling the crowd, you know, we’re peacefully protesting, don’t do these actions,” Ernst told reporters. “But does that mean he is guilty of inciting insurrection? And there is a very specific legal definition for that…I don’t believe that maybe it does meet that definition, but again I’ll listen to those arguments, but the broader question is is it constitutional.”

A Congressional Research Services report found that most scholars agree that a president can be impeached after they leave office. 

Grassley said in a Jan. 21 interview with The Daily Iowan that he does not think holding a trial would unite the country, something President Joe Biden promised to do in his inaugural address. He also questioned the validity of holding the trial after the president leaves office.

“It’s one thing, according to the constitution, to impeach a president, but can you impeach a citizen?” he said. “Because now it’s not President Trump, it’s citizen Trump.”

The trial will continue this week, and so far no witnesses have been called to testify, and Trump will also not be testifying.