Mark Kirk was the Republican Party’s last link to its origins as the Party of Lincoln. As a Midwesterner who stood for both social justice and economic opportunity, he represented two ideals that once defined Republicanism, but no longer coexist in today’s party.

Of course, the last Lincoln Republican had to come from the same state as the first one. Illinois has never allowed ideology to get in the way of a good political deal, and Kirk saw himself as the avatar of our state’s tradition of pragmatic Republicanism. In his Senate office, he hung a portrait of Senator Everett Dirksen, who collaborated with Lyndon Johnson to pass the Civil Rights Bill of 1964, corralling enough Republican votes to end a 57-day filibuster by Southern Democrats.

“You’re worthy of the Land of Lincoln,” Johnson told Dirksen.

Fifty years later, Kirk was the second Republican senator to come out in favor of same-sex marriage, and the first to co-sponsor the Equality Act, to ban discrimination against gays and lesbians. Gay rights is the civil rights issue of our time, and Kirk saw himself “carrying the mantle of Everett Dirksen.”

I voted for Kirk in 2010 because I thought he would be more independent of his party than his Democratic opponent, the callow Barack Obama wannabe Alexi Giannoulias. He never disappointed me. After the massacre of 20 children and six teachers at Sandy Hook Elementary School in Connecticut, Kirk was the only Republican to endorse President Obama’s gun control proposals. This year, when Obama chose Lincolnwood native Merrick Garland to replace the late Antonin Scalia on the Supreme Court, Republicans refused to act on the nomination, declaring the vacancy should be filled by the next president. Kirk was the first Republican senator to meet with Garland, putting him on the spot by asking him, “Lou Malnati’s or L. Woods?” Kirk also formed a close friendship with West Virginia Senator Joe Manchin, a red state Democrat forced to reach across the aisle from the other direction.

Kirk was one of the first Republicans to break with Donald Trump, declaring in June that “he does not have the temperament to command our military or our nuclear arsenal,” and calling him “a malignant clown” after hearing the Access Hollywood tape in which Trump boasted of grabbing women “by the pussy.”

On the other hand, Kirk was one of his party’s leading Iran hawks, comparing the nuclear deal with the ayatollahs to the appeasement of Nazi Germany before World War II. He called Obama the “drug dealer in chief” for releasing $400 million in seized assets to the country. Kirk was also an opponent of the estate tax, and high taxes on capital gains.

Kirk honed his talent for bipartisanship in ten years as the representative of the northern suburbs’ 10th Congressional district, which is so closely divided between Democrats and Republicans it has switched parties in each of the last three elections.

“I always sought to be a representative of that moderate, Midwestern, practical, incremental, ‘let's get ’er done’ crowd of the American people. It was a frustrating thing to see the country torn between far right and far left and going into a state of inaction,” he told the Tribune last week. “There is truth in both parties. Democrats are true in being socially tolerant. Republicans are true in being so fiscally conservative. And that is a necessary balance for the country to move forward in the 22nd century.”

The Midwest is no longer the heartland of Republicanism, as it was in the time of Lincoln and Dirksen: the party is now dominated by neo-Confederate Southerners who view any compromise as the equivalent of surrender. In spite of his social tolerance, Kirk’s party label doomed him to defeat in his re-election campaign against Tammy Duckworth: this year, for the first time, every state voted for the same party in the presidential and Senate elections.

I was planning to vote for Kirk again until that bizarre debate moment in Springfield when he mocked Duckworth’s Thai ancestry. After she boasted that her family’s military service dated back to the American Revolution, he retorted, “I forgot your parents came all the way from Thailand to serve George Washington.” Duckworth defeated Kirk 54.9 percent to 39.8 percent, the worst loss for an incumbent senator in Illinois’s history.

Kirk was never the same after the 2012 stroke that kept him away from the Senate for a year. Whether that contributed to the Thai remark, or to calling bachelor senator Lindsey Graham, a “bro with no ho… that's what we say on the South Side,” I can’t say. It did contribute to the Tribune editorial board, which could not have invented a senator that suits its philosophy better than Kirk, declining to endorse him for re-election. His health prevented him from “perform[ing] to the fullest the job of a U.S. senator,” the newspaper wrote.

When Kirk was elected, I hoped he and Dick Durbin would become a modern-day duo like Dirksen and Paul Douglas, long-serving Illinois senators from different parties who collaborated on such landmark legislation as civil rights and environmental protection. But Dirksen and Douglas served together in the 1950s and ’60s, the middle decades of a century defined by a prosperous middle class and a politics in which each party represented a broad spectrum of opinion, and was able to find common ground with the other.

Those politics are gone, replaced by parties that represent the far left and the far right, with views reinforced by partisan cable channels and websites. Gone, too, is a place for a senator like Mark Kirk.