Politics are on the menu here at The Coffee Tree Roasters.

At a patio table early one sunny August morning in this leafy Pittsburgh suburb, a quartet of friends debated President Donald Trump’s latest headache - the guilty plea by his longtime lawyer and personal fixer Michael Cohen. 

Inside, newspapers are piled high on cafe tables. And men and women in suits huddle in serious conversation over steaming coffee mugs and pastries.

It’s a fitting enough setting for a nationally watched congressional race that may not only determine control of the U.S. House in 2019, but may well also be an early indicator of whether President Trump’s 2016 win in a key Rust Belt state was an aberration or a genuine shift in a state that had been Democratic blue for three decades.

Nestled in Pittsburgh’s South Hills, Mt. Lebanon (pop. 32,349) is one of the critical battlegrounds in the fight for Pennsylvania’s redrawn 17th District. It’s a race that pits two incumbent congressmen, Democrat Conor Lamb and Republican Keith Rothfus, against each other in the ultimate survival match.

“This is a great race to watch,” said Joseph DiSarro, a political science professor at Washington & Jefferson College in Washington, Pa., who’s been monitoring congressional contests in southwestern Pennsylvania for years. “You have candidates with contrasting styles. And this is an area that’s in transition.”

While the greater Pittsburgh region has largely shed its industrial past, there are still pockets of blue-collar poverty, filled with voters who gravitated to Trump in 2016.

The 17th District is also one of at least six Pennsylvania districts that could hand national Democrats a portion of the 23 seats they need to recapture the majority in the U.S. House. 

It’s well known that Trump considers Pennsylvania a jewel in his 2016 campaign crown. It’s equally well-known that Democrats want it back.

Lamb, 34, a former Marine and federal prosecutor, first captured public attention in March, winning a special election in a district that Trump carried by 19 points just two years ago.

Lamb narrowly defeated Republican state Rep. Rick Saccone, a culture warrior who styled himself as “Trump before Trump,” and had the backing of the White House.

Shortly after that win, a congressional map imposed by the state Supreme Court thrust Lamb into the new 17th District, where the 56-year-old Rothfus, himself an early Trump supporter, had been the incumbent since 2012.

The new seat is far friendlier to Democrats. Had it existed two years ago, Trump would have carried it by a slender 2.5 percent, compared to the 20 percent margin he notched in the current 12th District, which will blink out of existence come January.

Indeed, Rothfus coasted to victory in the seat in 2014 and 2016, easily turning away Democratic challenges. It won’t be as easy this time. Both sides expect a torrent of outside money and the same wall-to-wall coverage that marked last spring’s special election.

So far, reliable polling in the race has been scarce. Lamb led Rothfus 51-39 percent in a July 24 Monmouth University poll. The margin is likely to tighten between now and Election Day, though some are skeptical on how much. 

In Lamb, who is pro-labor, pro-Second Amendment and personally opposed to abortion (though he doesn’t think new laws are needed), Democrats hope they’ve found a template to win back their voters who crossed over to Trump in 2016.

“This is a House seat traditionally held by moderates,” said Pittsburgh-based Republican consultant Dennis Roddy said. “It’s when people go outside that, that they get into trouble.”

Rothfus, whom DiSarro describes as a “Wall Street Republican,” remains popular with base voters throughout the district. And, he added, Rothfus “is not Rick Saccone,” who ran what was widely considered a lackluster campaign that not even a presidential visit could salvage.

But it’s also been a while since he’s had to break a sweat. And to that end, Rothfus recently launched his first ad of the campaign.

Lamb has yet to get into the air wars, but he’s out on the trail, meeting and talking to voters.

“The biggest thing we’re hearing from people is that they’re tired of the gridlock and want Washington to work,” Coleman Lamb, the candidate’s younger brother, and spokesman, said in an interview. “[Conor] will do that. He’s not one for inaction. And that, more than anything, is what people are responding to.”

With about six weeks to go before Election Day, the race will come down to that political alchemy of voter outreach, money, advertising and enthusiasm. 

“It’s a race between the tortoise and the hare,” Roddy reflected. “And this time, the hare won’t take a nap.”

An award-winning political journalist, Micek is the Opinion Editor and Political Columnist for PennLive/The Patriot-News in Harrisburg, Pa. Readers may follow him on Twitter @ByJohnLMicek and email him at jmicek@pennlive.com.