Former Indiana Sen. Richard Lugar died Sunday at the age of 87.

Lugar, a centrist Republican best known for his foreign policy expertise, represented Indiana in the Senate for 36 years, losing his seat in 2012. He was chairman of Senate Foreign Relations Committee from 2003 to 2007. He died from complications arising from chronic inflammatory demyelinating polyneuropathy, the Lugar Center announced.

He had a soft-spoken demeanor and was lauded for his ability to work across the aisle on complicated foreign policy issues, such as his 1990s attempt with Sam Nunn, a Democratic senator from Georgia, for a disarmament program in the former Soviet Union. He was described by the New York Times as "a collegial moderate who personified a gentler political era."

Lugar tried to leverage that reputation into a 1996 run for president with the slogan “nuclear security and fiscal sanity." But he failed to gain traction and dropped out early. Sen. Bob Dole of Kansas went on to secure the GOP nomination, but lost the general election to President Bill Clinton.

He lost to Republican primary challenger Richard Mourdock, a Tea Party candidate, in 2012, when he was 80. During a bitter campaign, it had emerged he was registered to vote at a home in Indianapolis he had sold in 1977 when he first became a Senator — a revelation that underscored his image as a denizen of Washington who had strayed from his Indiana roots. Mourdock lost in the general election.

In 2013, President Barack Obama presented Lugar, whose ties to him had harmed him in his primary campaign with the Presidential Medal of Freedom, the highest U.S. civilian honor. “Dick Lugar's decency, his commitment to bipartisan problem solving, stand as a model of what public service ought to be,” Obama said.

Nunn hailed Lugar in a Sunday statement. “Our nation has lost an extraordinary statesman who made the world a safer and better place. I have lost a wonderful friend and trusted partner. Dick Lugar treated every person with dignity and respect. This generation and future generations can learn much from his example in the political world and in life."

Prior to his time in national politics, Lugar served as mayor of Indianapolis, Ind., from 1968 to 1976. He was recognized by the current mayor in a pair of tweets.

"[Lugar] understood that progress could only occur when good ideas and good people came together -- from all sides of the political landscape. And he demonstrated a commitment to country over party, community over self, that is almost unparalleled in today's polarized world," Mayor Joe Hogsett said.



He understood that progress could only occur when good ideas and good people came together -- from all sides of the political landscape. And he demonstrated a commitment to country over party, community over self, that is almost unparalleled in today's polarized world. pic.twitter.com/5kc3xOkXmD — Mayor Joe Hogsett (@IndyMayorJoe) April 28, 2019



Senate Minority Leader Chuck Schumer, D-N.Y., also praised Lugar for his dedication to bipartisanship. "Dick Lugar personified the thoughtful bipartisanship so much missing in America today. He will be missed," Schumer tweeted.



Dick Lugar personified the thoughtful bipartisanship so much missing in America today.



He will be missed. https://t.co/3TA1VMgEZ0 — Chuck Schumer (@SenSchumer) April 28, 2019



"Saddened by the news that Senator Richard Lugar has passed away. He served our country honorably in the Navy, and he represented Indiana proudly for decades in the Senate. Please keep his family in your prayers," Republican National Committee chair Ronna McDaniel tweeted.



Saddened by the news that Senator Richard Lugar has passed away.



He served our country honorably in the Navy, and he represented Indiana proudly for decades in the Senate.



Please keep his family in your prayers. — Ronna McDaniel (@GOPChairwoman) April 28, 2019



Pete Buttigieg, mayor of South Bend, Ind., and a 2020 Democratic candidate, saluted Lugar. "America has lost a true statesman in Dick Lugar. A great mayor, senator, and mentor, he made the world safer, stood up for better foreign policy, and knew how to work across the aisle," he said. "He was never too important to make time for a young Hoosier public servant of either party. And I have never seen a Senator’s office so filled with books."

Indiana Gov. Eric Holcomb said "the world weeps" over Lugar's death. "He was an officer and gentleman, father and faith leader, a Mayor and Senator, a diplomat and legendary role model to millions. @FLJanetHolcomb and I are keeping Mrs. Lugar and their wonderful family in our prayers and ask all those touched by his service to join us," he said in a string of tweets.