Updated 3:36 p.m. | Illinois Rep. Lauren Underwood had been fielding questions from a mostly friendly audience at a recent town hall when she was confronted with a challenge.   

Which was worse, a man who identified himself as Robert from Woodstock, asked the freshman lawmaker — the yearbook photo showing her “Democratic colleague,” Virginia Gov. Ralph Northam, wearing blackface, or his position “in favor of infanticide?”

The question, captured on a Facebook Live broadcast, was a rare flash of hostility in a series of public events that Underwood and her fellow freshman Democrat Sean Casten have held together in recent weeks in neighboring districts in Chicago’s western suburbs that had been represented by Republicans for decades. It was also a reminder that some of their constituents view them as impostors.

Underwood and Casten — like many other Democrats who flipped suburban seats last fall — will be on the front lines of the Democrats’ fight to hold on to their House majority in 2020, and to reaffirm that the country’s suburbs are shifting to the left. Just a few months into their terms, the battle lines are already forming.

A growing pack of potential challengers to Underwood in the 14th District and Casten in the 6th is circling. The House Democratic and Republican campaign arms have identified the districts as top 2020 battlegrounds.

Meanwhile, Casten and Underwood, like other Democrats in swing districts, are working hard to show their independence. That effort will be complicated as their potential opponents and some skeptical constituents seek to tie them to the more inflammatory actions and positions of their Washington colleagues — like the Green New Deal and “Medicare for All” — that are drawing the party to the left.

“They are going to have to answer for their increasingly radical caucus,” National Republican Congressional Committee spokesman Chris Pack said. “If you’re not speaking out against that crazy stuff, you are a part of that crazy stuff.”

Onstage at McHenry County College, after the hisses and applause died down, Underwood adjusted herself in the bar-height chair, took a deep breath, and made her pitch.

“I wholeheartedly reject all forms of racism,” said Underwood, who is African-American. She then turned to the second part of the question, which referred to a recent debate over late-term abortions. A registered nurse, Underwood said she believes a woman has “an unrestricted right to the full range of reproductive health care services.” That line earned even stronger applause.

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Lining up

With about a year to go until primary elections in Illinois, it’s still anyone’s guess how many Republicans will end up running. But a number of high-profile candidates have already indicated strong interest in both districts.

That list was fortified earlier this month, when former Lt. Gov. Evelyn Sanguinetti said at a county chairman’s annual Corned Beef & Cabbage bash that she was “seriously thinking” about challenging Casten in the 6th District. DuPage County board member Greg Hart has also been mentioned as a possible contender.

Political strategists from both parties cited Sanguinetti’s name recognition and familiarity with donors as strengths. While she was on a losing statewide ticket with Republican Gov. Bruce Rauner last fall, they carried the 6th District. Her connection to the unpopular Rauner, though, could be a liability, the strategists said.

In the 14th, the list is longer. Jim Oberwiess, a dairy magnate and state senator who’s lost multiple previous bids for the Senate and House, is in. Other declared candidates include Navy veteran Matt Quigley, Army veteran Anthony Catella and HR manager Danny Malouf. State Rep. Allen Skillicorn, who recently hosted a “fire Lauren Underwood pizza party,” has said he is considering a bid. Political strategists with ties to the area also floated state Sen. Sue Rezin as a strong candidate.

Pack, of the NRCC, said the party is “heavily recruiting,” but did not have any official names yet.

Whoever runs, he said, the Republican strategy, as in many swing districts, will involve trying to tie the incumbents to their more progressive colleagues, like Alexandria Ocasio Cortez, who have shot to stardom in the House.

Democrats countered by saying Republicans running in these districts would be “tainted” by their party’s national agenda. 

“Representatives Casten and Underwood have already established themselves as strong independent voices in Washington for lowering health care costs and ending President Trump’s tax hike on Illinois homeowners,” Democratic Congressional Campaign Committee spokesman Mike Gwin said.

The battlegrounds

The 14th and 6th districts have a lot in common. Voters in both tend to be white-collar and well-to-do. Both districts were drawn by the Democrat-controlled state Legislature following the 2010 census to favor Republicans.

But the Democratic victories there in 2018 were seen as evidence of the growing national rural-urban divide, and also as a referendum on President Donald Trump.

Hillary Clinton carried Casten’s seat by 7 points in 2016, while Underwood’s district, which includes more rural parts, backed Trump by 4 points. Those results have some strategists thinking the latter could be an easier target for the GOP this time around. But insiders in both parties also pointed to Underwood as the more formidable opponent, citing her reputation as a disciplined campaigner.

Inside Elections with Nathan L. Gonzales rates the 6th District race Leans Democratic and the contest in the 14th a Toss-up.

Republican challengers in both districts will have hurdles to scale: They will have to pay the daunting rates for Chicago-area advertising and be prepared for Democrats across the country to pour money into keeping the seats. The DCCC has already announced that Chicago’s western suburbs will be a focus of its “multimillion” dollar plan to start early field work in communities across the country.

But with a presidential race at the top of the ticket, there might not be as much money to go around, which could be a potential challenge for Casten and Underwood.

“Democrats who run successfully in suburban Chicago tend to present themselves as more moderate,” said James Slepian, an ad-maker and adviser to GOP campaigns. “Democratic presidential candidates seem to be adopting more extreme positions on the left. That puts those districts in play, as long as Republicans nominate candidates who are more credible and can speak to voters in the middle.”

For their part, Underwood and Casten are both working to strike their own balance.

At an earlier forum in February, Underwood said it was great that the country was talking about the high costs of health care, but she felt the presidential candidates who have embraced Medicare for All didn’t seem to have a uniform definition. “My challenge is how much is it going to cost and how we are going to pay for it,” she said.

Casten, a former president of an energy company, spent his earlier career working to help reduce greenhouse gas emissions. At the event with Underwood, he called the Green New Deal an “activist-led agenda,” driven by groups on the “farther left of the party” with “noble goals.”

“You can love baseball and not like the St. Louis Cardinals,” he said.