When Steve Scalise served in the Louisiana House of Representatives, two of his three roommates were Democrats. At night, the four of them attended legislative receptions together — and even fundraisers for one another — ignoring the partisan divide.

But during the day, Scalise, a Republican, stood well apart from most of his House colleagues as he pushed a strongly conservative agenda, one that enjoyed little support when he arrived in Baton Rouge in 1996 but was becoming increasingly popular by the time he departed in 2008.

The most effective lawmakers in Baton Rouge learn that success comes from not personalizing their political differences with colleagues. But few have practiced that philosophy better than Scalise, who was shot by a gunman on Wednesday in suburban Washington, D.C., and was recovering following surgery to his hip.

“We would fight during the day,” said one of his roommates, Troy Hebert, of Jeanerette, who was then a registered Democrat. “But he had a knack of being against people without being disagreeable. He was never in your face. You can’t help but like him.”

Scalise left the state House when he was elected to the state Senate in 2007, and a year later, he was elected to the U.S. House of Representatives. Only seven years later, Scalise vaulted dozens of more senior Republicans when his colleagues elected him majority whip, the No. 3 position within the GOP leadership.

“What separated Steve from everyone else — he was very, very focused,” said Rick Legendre, who headed U.S. Rep. Bob Livingston’s congressional office in Metairie in the 1990s and later worked for Scalise.

In a 2015 interview, Scalise said serving in the Louisiana House was a good training ground for his meteoric political rise. Lawmakers there work in close quarters with one another. They have only a single aide and don’t have an office unless they chair a committee. The House may plow through 50 votes in a single day.

“It’s hand-to-hand combat on the House floor,” Scalise said. “As soon as that battle is over, they gavel it down and then they bring up the next bill right away. There is no cooling-off period. If you’re holding a grudge against somebody over the battle you just went through, you might be working with them on the next bill. If you make your disagreement personal, you’re not going to be able to get them to help you get the next battle won. If you’re making enemies along the way, you’re going to limit the ability for yourself to be successful in advancing your causes.”

Indeed, Scalise is something of a paradox. He helped pull the state House rightward in Baton Rouge while he sought greater restrictions on abortion, more rights for gun owners, fewer government controls over business and a ban on gay marriage in Louisiana. In Washington, he champions the conservative but divisive congressional agenda led by Speaker Paul Ryan.

Yet he has earned an unusually low number of enemies along the way.

That probably saved his job as majority whip after Lamar White Jr., a liberal Louisiana-based blogger, revealed in late 2014 that a dozen years earlier, Scalise, then still a state representative, had addressed a white supremacist group founded by David Duke, the neo-Nazi sympathizer who was grand wizard of a Ku Klux Klan faction in the 1970s and was later elected to represent Metairie for a single term in the state House. Duke did not attend the event.

White’s post became national news and led to calls that Scalise ought to resign. But no evidence emerged to tie Scalise directly to Duke. And more importantly, perhaps, while Scalise was the focus of intense scrutiny, several prominent African-Americans in New Orleans defended him — including U.S. Rep. Cedric Richmond, a Democrat who now leads the Congressional Black Caucus.

“I don’t think Steve Scalise has a racist bone in his body,” Richmond told The Times-Picayune. “Steve and I have worked on issues that benefit poor people, black people, white people, Jewish people. I know his character.”

Bill Goldring, a liquor magnate and major philanthropist, invited Scalise to meet with 25 local Jewish leaders, many of whom arrived with concerns because of the news accounts, Goldring recalled on Wednesday. But those concerns faded after Scalise spent an hour answering questions in Goldring’s Metairie Road office.

“After the meeting ended, everyone was 1,000 percent convinced who the real Steve Scalise was, that he was definitely not-anti-Semitic,” Goldring said.

The furor quickly died down nationally, but not before Duke called Scalise a “sellout” for denouncing him. Since then, Scalise has continued to play a critical role in advancing the Republican agenda in the House of Representatives, especially with Donald Trump as president.

Scalise, 51, who is married and the father of two young children, is the son of a real estate broker and a homemaker of Sicilian heritage who was active in the state Republican Party.

“He comes from a long line of people who are engaging and who you can work with,” said Ben Bagert, a former Republican state legislator from New Orleans who shares the same great-grandparents. “He likes politics because he likes to be in the fray, but he wants to do consequential things.”

After attending Archbishop Rummel High School, Scalise became the family’s first college graduate, with a degree in computer programming from LSU. He went on to work for a local company owned by Bobby Savoie, who in 2012 hosted a re-election fundraiser at his home for President Barack Obama.

“Steve is a techie, but he is absolutely not a nerd when it comes to people skills,” Savoie said.

When Quentin Dastugue chose not to seek re-election in 1995, the state Republican Party recruited Scalise, then 29.

Gina Goings, who had just gotten a master’s degree in political communications from the University of New Orleans, was among those who worked for Scalise’s campaign.

“Steve was relentless,” Goings said, and Scalise won easily.

Scalise was relentless about pushing his conservative causes, which meant he frequently butted heads with Gov. Mike Foster, a moderate Republican, and Gov. Kathleen Blanco, a Democrat.

While in the state House, Scalise set his sights on running for the 1st Congressional District. In 1999, then-state Rep. David Vitter jumped into the race to replace Livingston, who resigned suddenly over a sex scandal, effectively keeping out Scalise. When Vitter decided to run for the U.S. Senate in 2004, Scalise began organizing a campaign. The year before, Scalise had stuck his neck out to endorse Bobby Jindal, the brainy young Republican running who was a longshot candidate for governor. Jindal came on strong and only narrowly lost the governor’s race.

Scalise’s reward for his support in 2004? Jindal moved from Baton Rouge to the 1st Congressional District and proved so formidable that Scalise had to drop out of the race. Scalise was bitterly disappointed, but he was thinking about the long run.

“I didn’t think he’d stay there that long if he won,” Scalise said, looking back. “I decided to pull back and fight to win another day.”

That day came in 2008 when Jindal resigned his congressional seat after being elected governor, and Scalise won a special election to replace him.

Although deeply conservative, Scalise did not join with the Republicans who wanted to shut down the government, such as Republican Sen. Ted Cruz, of Texas.

“Maybe throwing a Hail Mary might seem like a good option to you,” Scalise said of Cruz’s tactics, “but I’d rather get a 20-yard completion.”

He also would rather build and maintain friendships with those who disagree with him.

“He’s not an angry guy that sometimes you find,” said state Sen. Mike Walsworth, a Republican from Monroe who also roomed with Scalise when both were in the state House. “He’s got a good nature about him.”

Even after his rise to one of the most powerful jobs in Washington, Scalise has continued to move around his district in the same unassuming way as before, often stopping at a PJ’s in Metairie for his morning coffee. He pops out of a black SUV with his security detail, sometimes in a suit, sometimes in shorts and a golf shirt. He is always quick with a kind word, but is rarely in campaign mode, preferring to blend in and share conversation with friends and neighbors.

During Carnival, Scalise can often be seen on St. Charles Avenue with a neck full of beads.

The morning after Republicans swept Congress, Scalise was in a corner of a PJ’s on a conference call with other GOP leaders, giddy with excitement over the potential to push through a conservative agenda. The first order of business, he told a reporter who wandered in, was dismantling the Affordable Care Act, a gambit the House, at least, was able to pass, on a party-line vote.

On Wednesday, the baristas at the coffee shop, who know him by name, expressed shock at the news that their powerful but unpretentious regular had been shot.

“I still call him Steve,” said Goings. “I know I should address him differently. But if I called him Congressman, he’d think it was a joke.”

Staff writer Martha Carr contributed to this report.

Follow Tyler Bridges on Twitter, @tegbridges.