Many of those same Republicans — who lived for nearly five decades under GOP Reps. Henry J. Hyde and Peter Roskam — had never had a Democratic representative in their lifetime.

But even more than that, they never thought that this particular Democrat would be leaning so forcefully into an impeachment inquiry against a Republican president.

Casten is among those who’ve been dubbed “frontliners” by their party — freshman Democrats whose victories last year were a hallmark of the blue wave that wiped out suburban GOP incumbents and who face uphill re-election battles in 2020. Many frontliners tend to tiptoe around the politically thorny issues of the day like impeachment, knowing that their stance could make them a one-term lawmaker and, in turn, cause Democrats to lose their House majority.

Casten has chosen a different route.

INTERACTIVE: See where House lawmakers stand on impeachment

The soft-spoken lawmaker was one of the first vulnerable Democrats to come out in support of an impeachment inquiry. And despite the political risks, he is embracing it more than anyone on Capitol Hill right now.

Casten, a 47-year-old former energy executive who ran on climate change, is a relatively unknown entity in Washington. He shuns the limelight and isn’t a fixture on cable news like some of his fellow freshmen. But here in his C-shaped district west of Chicago, he has put himself in the spotlight more than any other first-term Democrat — in part because he knows it won’t be easy to win again here in 2020.

When I met up with him for an interview on Saturday morning, he had done 13 town hall events since taking office in January. By 8:30 p.m., that number stood at 19, after a grueling day crisscrossing the bellwether district and taking voters’ questions for six hours.

Over the summer recess, Casten held a town hall event focused exclusively on impeachment. Before lawmakers left Washington for the six-week break, he implored his fellow freshmen during a closed-door meeting to hold similar events. They all thought he was crazy.

But in some respects, that was to be expected for someone who came out in support of an impeachment inquiry against Trump in June. In fact, he was one of the first frontliners — along with Reps. Tom Malinowski (D-N.J.) and Katie Porter (D-Calif.) — to back such a process.

When they were preparing to go public, the three of them asked to meet with Speaker Nancy Pelosi. They wanted to give her the courtesy, Casten said, because their support of formal impeachment proceedings had the potential to muddy Pelosi’s cautious strategy at the time.

“To her credit, she said, ‘You don’t need my permission; you just need to do the right thing for you,’” Casten told me, about the previously unreported meeting.

Pelosi stuck to her “investigate, legislate, litigate” strategy even as a majority of her caucus was supporting an impeachment inquiry. At the time, it was special counsel Robert Mueller’s report on Russian interference in the 2016 election — and evidence he uncovered showing that Trump sought to obstruct the probe — that was driving Democrats to support formal proceedings.

It wasn’t until an entirely different scandal surfaced that Pelosi decided to finally embrace an impeachment inquiry. In the less than two weeks since she formalized the impeachment process, House investigators are rapidly intensifying their efforts to highlight what Democrats say is damning evidence that Trump abused his office to solicit foreign assistance to dig up dirt on his political rivals.

The end of September was an inconvenient time for lawmakers to leave Washington for a two-week recess, just days after Pelosi formalized the House’s impeachment inquiry and investigators began collecting evidence and subpoenaing witnesses in earnest. So it presented Casten and other vulnerable Democrats with a challenge as they face the music from voters back home.

At each of his events on Saturday, Casten emphasized what he called the “somberness of this moment.”

“If you, in your head, would celebrate impeachment or would celebrate exoneration, you’ve got to straighten out your head,” he said. “There’s nothing to celebrate about the moment that we’re in.”

“We have been forced into this by the circumstances,” he added.

After a grueling stretch listening to voters grill Casten, here’s what I learned about Democrats’ months-long trod toward impeachment proceedings.

You can’t move public opinion toward impeachment if you don’t embrace it.

For Casten, the June meeting with Pelosi was prescient. He told the speaker that the polling on impeachment — which was abysmal at the time — was irrelevant to him until Democrats had a united front convincing the public that impeachment would be worth looking at.

“I can’t get out there and educate the voters if they say, ‘Well, given all of this stuff, why aren’t you in favor of starting the impeachment process?’” Casten said. “I said, well, basically, I want to get out to a point where I can educate the voters — and so that was really my motivation for coming out, because I wanted to be some force of education.”

Casten backed impeachment proceedings on June 20. Over the next three months, Pelosi stuck to her strategy, even as more of her Democratic colleagues broke ranks. The polling on impeachment remained stagnant — until two weeks ago, when the speaker reacted swiftly to Trump’s admission that he asked President Volodymyr Zelensky of Ukraine to investigate former Vice President Joe Biden, Trump’s potential opponent in the 2020 election.

“What we’ve seen over the last couple weeks is that once the party gets behind this, the polls move,” Casten said. “Because at the end of the day, I think people are generally more motivated by truth than lies. But we haven’t been out there telling that story.”

Pelosi’s critics — particularly those on the progressive left who have been girding for impeachment proceedings since the day Mueller’s report was released — have touched on similar arguments in recent months to make the case that public support for impeachment wouldn’t magically grow through House Judiciary Committee hearings on the legalese surrounding obstruction of justice. They accused Democratic leaders in particular of dithering as they failed to sustain momentum amid the White House’s all-out blockade of subpoenas seeking documents and witness testimony, forcing House Democrats into the arduous and slow federal court system to seek compliance.

In the end, though, it took an entirely different scandal to get Pelosi to “yes” — one that has united Democrats in outrage and one that is markedly easier to portray as an impeachable offense.

“I find in this job, you can do the work in Washington. But you really can’t move public opinion very much,” Casten told me. “When you’re in the district, you’re not voting on stuff, you’re not going into committee hearings. But you can move public opinion.”

“So the bully pulpit that I have is much more effective in the district than nationally right now,” he said.

In the meantime, Democrats are trying — with varying degrees of success — to push back on Trump’s unproven claims about Biden’s efforts to remove a controversial Ukrainian prosecutor, and the president’s fixation on a debunked theory that Ukraine, not Russia, interfered in the 2016 election.

At five of Casten’s six town halls on Saturday, he was pressed on those claims.

Trump’s claims about Biden are resonating among his political base.

This one may come as no shocker, since the president’s base of voters has remained loyal to him through scandal after scandal, transgression after transgression.

But Trump’s efforts to paint Biden as corrupt for trying to oust a prosecutor who at one point was investigating a company tied to his son Hunter appeared to resonate among his supporters who attended Casten’s town halls — some of whom were wearing “Make America Great Again” hats and “Trump 2020” t-shirts.

Casten was prepared for those inquiries. Right off the bat at his first town hall here, a woman tore into Pelosi and Rep. Adam Schiff (D-Calif.), the chairman of the House Intelligence Committee, accusing them of “lying their little butts off” and saying that a whistleblower’s complaint about Trump’s interactions with Ukraine’s president “looks like a bunch of 13-year-old girls gossiping.”

Constituent Steven Wood and his wife accused Rep. Sean Casten of cheapening the political discourse by deriding Trump’s immigration policies as “racist” and referring to Trump’s claims about Biden as “crackpot conspiracy theories.” | Andrew Desiderio/POLITICO

At an event later in the day in Bartlett, Ill., a constituent asked Casten why he wasn’t condemning Biden’s actions.

In both instances, Casten spoke for more than five minutes about the nitty-gritty of the claims Trump and his allies have made about Biden. He unapologetically declared that there was “no ‘there’ there on the Biden story,” and after hearing a question about the unsubstantiated theory that Ukraine was responsible for meddling in the 2016 election, he told the voter that she was espousing a “deep-down-the-rabbit-hole, crazy conspiracy theory.”

Casten’s posture toward impeachment comes with real political risks.

Republicans have lost significant ground in districts like Casten’s in the Trump era — districts that were once the anchor of the GOP. The party has struggled to retain support among suburban moderates, women and minorities in particular, and in 2018 the GOP lost many of these seats in the suburbs of Philadelphia, Chicago and Los Angeles .

Republicans’ strategy for winning back the House in 2020 is to tie Democrats like Casten to the more progressive voices in his party and make the case that they are too extreme for their districts — from their support for impeachment to their rhetoric about the president.

So even though Democrats like Casten are confident in their pushback against Trump and his allies, the terrain in historically conservative districts like this one remains fraught with political landmines — ones that Casten tacitly acknowledged, even as he tore into Trump on issues completely unrelated to impeachment.

“If the president screwed up, at the end of the day he’s got to be gone,” Steven Wood told me after confronting Casten as he was leaving his town hall in Fox River Grove, Ill.

But Wood remains convinced that Trump did nothing wrong, and he took issue with the way Casten described the president’s claims about Biden, in particular his declarative statement that Trump and his supporters are “actively suppressing facts.” I witnessed the heated exchange, during which Wood and his wife accused Casten of cheapening the political discourse when he derided Trump’s immigration policies as “racist” and referred to Trump’s claims about Biden as “crackpot conspiracy theories.”

“People who ignore their morals and their ethics in order to support something or ignore the facts to support a reprehensible morality, I’m not going to pretend to — ” Casten told Wood as a staffer intervened to whisk him away to his next town hall.

Casten later told me that he’s unapologetic about both his stances and his rhetoric because anything else would be a betrayal to his true self. At the same time, though, he risks alienating Republicans who might otherwise support him.

“The partisan affiliation of the district is massively less relevant than the morality of the district,” Casten said. “I voted for George H.W. Bush. I voted for Bob Dole. I don’t think my morals have changed. But I don’t think those individuals are very well represented by the existing elected members of the Republican Party.”

“I would rather,” he added, “be a politician who says, these are my non-negotiables, and if you like it, vote for me, and if you don’t like it, don’t vote for me, than someone who says I’ll be morally ambiguous and I’ll just blow back and forth to wherever the public goes. Because that ain’t me.”

However, Casten made some implicit overtures to Republicans each time he was confronted over the Ukraine scandal. At nearly all of the six town halls, he said there was at least one area in which Trump had done a better job than Barack Obama: his willingness to arm the Ukrainians with lethal defensive weapons as they fight back against Russia’s aggressive incursions into Eastern Europe.

Despite impeachment fervor, voters still care about policy agendas.

Impeachment is all-consuming on cable news and in the national press — and for good reason. But many liberal voters across Illinois’ 6th Congressional District, while supportive of the impeachment effort, don’t want policy priorities like gun control and climate change to take a back seat. At one of the town halls, impeachment didn’t come up even once.

Gun-control legislation is still languishing amid Trump’s apparent opposition to tightening background checks; the U.S.-Mexico-Canada trade agreement remains stalled amid negotiations with House Democrats; and lawmakers have yet to act on bipartisan, comprehensive immigration reform.

It’s a reflection of Pelosi’s long-held view that Democrats won control of the House in 2018 not because of impeachment, but because of their focus on kitchen-table issues like health care. Pelosi often reminds her members that they can walk and chew gum at the same time.

To be sure, at four of the six town halls, voters spent the majority of the session asking about issues related to impeachment. It’s exactly what Casten expected, and he came prepared.

Everybody loves hammering the media.

Casten doesn’t call the press “fake news” or the “enemy of the people.” But at each town hall event, he singled out the national news media for portraying what he sees as a false narrative of what happens in Washington.

It’s a common refrain at town halls across America — rural or urban, liberal or conservative, rich or poor.

Casten knocked the media for what he sees as a portrayal of the Democratic Party as being controlled by the more progressive voices like Reps. Alexandria Ocasio-Cortez (D-N.Y.) and others who, he quipped, “have more Twitter followers than me.”

He made the point that Democrats won back the House not because of lawmakers like Ocasio-Cortez who ran to the left of incumbents, but because of the 39 freshman Democrats who flipped Republican-held districts and tend to be centrists.

“The part that I wish got more coverage,” Casten told me when I asked about his media criticisms, “is the fact that there is such massive ideological diversity in the Democratic Party, that it’s a big enough tent to accommodate from AOC and Bernie Sanders out to Dan Lipinski and Joe Manchin, and it means that on almost every policy conversation we’re having, the policy debate is happening in the Democratic Party.”

“On the other side of the aisle, you have from Peter King to Steve King,” Casten said, referring to two well-known Republican congressmen, the latter of whom has been shunned by his party for racist rhetoric. “They all sing from the same hymnal because they only own one book. The era when the Republican Party was really engaged in ideas is gone.”

At a town hall in Sleepy Hollow, Ill., a 69-year-old man pressed Casten to “push back on these crazies,” referring to the progressive “squad” of Ocasio-Cortez and Reps. Ayann Pressley (D-Mass.), Ilhan Omar (D-Minn.) and Rashida Tlaib (D-Mich.). In Glen Ellyn, Ill., another man confronted Casten about Omar’s comments about Jewish people, which were criticized as being anti-Semitic.

Casten drew applause when said that while he condemns “horribly inappropriate” remarks from members of his own party, “we are far too quick to condemn hatred when it comes out of a brown woman in a head scarf than we are when it comes out the mouth of a white supremacist.”

Casten might not like how those dynamics are portrayed on cable news, but his exchanges with voters who support the president almost felt like the heated cable news segments that sometimes go viral. Americans are having the same arguments at the local level, and it’s yet another reflection of how polarized the political climate has become.

