Freshman Rep. Sean Casten, D-Ill., has hosted about a dozen formal town halls so far, plus more sessions open to the public where he has taken questions.

The difference Wednesday night at the Downers Grove Village Hall is that Casten came specifically to discuss where things stood regarding the impeachment of President Donald Trump, a potentially provocative topic in this swing district.

Almost all of the seats were filled; about 170 people checked in. Anyone could have registered to attend. The event was livestreamed on Facebook with 2,900 views by Thursday afternoon.

Casten is one of the most vulnerable freshmen in Congress. If Casten wanted to play it safe, the obvious course would be to not do a town hall devoted to Trump’s impeachment.

It took a certain amount of guts to take the risk of hosting an impeachment town hall where he could have taken incoming fire and have the scene captured in an embarrassing video to be used against him.

He has two well-known Wheaton Republicans — former Lt. Gov. Evelyn Sanguinetti and former state Rep. Jeanne Ives — facing off in the March primary for the prize of running against him in 2020. Ives almost beat Gov. Bruce Rauner when she ran for governor in 2018.

A Downers Grove resident, Casten arrived on Capitol Hill in January, after beating former Rep. Peter Roskam, R-Ill., 53.6% to 46.4%. The 6th Congressional District hugs the Chicago suburbs and includes parts of Cook, DuPage, Kane, McHenry and Lake counties.

Casten on June 20 came out in favor of launching an impeachment inquiry against Trump. At the time, Casten told me he wanted to declare his position “in order to have a conversation with the public about what I know and why I’m concerned. I have to be honest about where I stood on this issue.”

And that conversation took place on Wednesday.

At the start Casten said he had a request.

“If in your head right now you are thinking that the impeachment of the president of the United States is a cause for celebration or the exoneration of the president of the United States in an impeachment trial is a cause for celebration, I want you to just mentally check out for a minute and come back when you have that thought out of your head,” he said.

“The fact that we have to have, are having this conversation right how is not a cause for celebration, it is moment of responsibility, it is a moment of truth, it is a moment of trying to make sure we have a shared set of facts.”

For 90 minutes, Casten talked about why he backed an impeachment inquiry and took questions. It was about the future of democracy and the concept that no one is above the law, he said.

“Part of the obligation of a representative is to represent you and know where your head is, and part of (my) obligation is to share with you where mine is and that’s why I’m here today,” he said.

For all practical purposes House Democrats on the Judiciary Committee have already launched an investigation that could lead to the Democratic-run House voting on articles of impeachment. It’s unlikely a trial in the GOP controlled Senate would result in a Trump conviction and removal from office.

It was easy to read the friendly room.

The people packing the village council chamber were all supporting an impeachment inquiry. A question asked several times was about the backfire potential on the 2020 presidential election if Democrats moved ahead on impeachment.

“Don’t know,” Casten said.

There was some concern about whether the White House, by ignoring Judiciary Committee subpoenas, was playing out the clock.

Gemma Johnson, a psychologist from Downers Grove, said, “I just don’t want us to run out of time.”

MORE CASTEN COMMENTS

On Thursday, Casten met with the Chicago Sun-Times and said: