In this 2013 file photo, Senate Armed Services Committee Chairman Sen. Carl Levin, D-Mich. asks a question of a witness during a hearing on Capitol Hill in Washington on legislation regarding sexual assaults in the military. Levin, a powerful voice for the military during his career as Michigan’s longest-serving U.S. senator, has died. The Democrat was 87. Levin’s family says Levin died Thursday. (AP photo)

DETROIT — Famous for gazing over eyeglasses worn on the end of his nose, Carl Levin seemed at ease wherever he went, whether attending a college football game back home in Michigan or taking on a multibillion-dollar corporation before cameras on Capitol Hill.

Michigan’s longest-serving U.S. senator had a slightly rumpled, down-to-earth demeanor that helped him win over voters throughout his 36-year career, as did his staunch support for the hometown auto industry. But the Harvard-educated attorney also was a respected voice on military issues, spending years leading the powerful Senate Armed Services Committee.

Despite his record tenure and status, he kept his role in perspective. At his direction, the portraits of all 38 senators who had served before or with him since Michigan’s statehood in 1837 were hung in his office conference room. Two empty spaces were reserved for future senators.

“I’m part of a long trail of people who have represented Michigan,” Levin said in 2008. “I’m just part of that history. The people coming after me … can pick up where I leave off, whoever they might be.”

The former taxi driver and auto-line worker, who for decades kept his faded 1953 union card in his wallet, died Thursday at 87. His family and the Levin Center at Wayne State University’s law school did not release a cause of death in an evening statement. He had been living with lung cancer since age 83.

“We are all devastated by his loss. But we are filled with gratitude for all of the support that Carl received throughout his extraordinary life and career, enabling him to touch so many people and accomplish so much good,” the statement said.

First elected to the Senate in 1978, Levin represented Michigan longer than any other senator, targeting tax shelters, supporting manufacturing jobs and pushing for military funding. His tenure was a testament to voters’ approval of the slightly rumpled, down-to-earth Detroit native whom Time magazine ranked among the nation’s 10 best senators in 2006.

“He’s just a very decent person,” Democratic Sen. Jack Reed of Rhode Island, a fellow Senate Armed Services Committee member, said in 2008. “He’s unpretentious, unassuming. He never forgets that what we’re doing is enmeshed with the lives of the people he represents.”

A Washington insider and former prosecutor known for his professorial bearing, Levin took a civil but straightforward approach that allowed him to work effectively with Republicans and fellow Democrats. He was especially astute on defense matters thanks to his years as the top Democrat on the Senate Armed Services Committee.

And he didn’t fear speaking his mind.

He was in the minority — even among his Democratic Senate colleagues — when he voted against sending U.S. troops to Iraq in 2002, and two years later he said President George W. Bush’s administration had “written the book on how to mismanage a war.” He gave a cautious endorsement to President Barack Obama’s 2009 buildup of troops in Afghanistan, but later warned of “the beginnings of fraying” of Democratic support.

He was also critical of President Ronald Reagan’s buildup of nuclear weapons, saying it came at the expense of conventional weapons needed to maintain military readiness.

But, colleagues said, he almost always engendered a feeling of respect.

“We’ve always had a very trusting and respectful relationship,” the late-Republican Sen. John Warner, who worked closely for years with Levin on the Armed Services Committee, once said. “We do not try to pull surprises on each other. The security of the nation and the welfare of the armed services come first.”

Famous for wearing his eyeglasses down on his nose, Levin seemed to be the same candid, hardworking guy wherever he went, whether he was in front of cameras on Capitol Hill, on an overseas fact-finding mission or lost in the crowd of a college football stadium on game day.

“No one would accuse Carl Levin of looking like Hollywood’s version of a U.S. Senator. He’s pudgy, balding and occasionally rumpled, and he constantly wears his glasses at the very tip of his nose,” Time magazine said in its 2006 article ranking the senator among the country’s best. “Still, the Michigan Democrat has gained respect from both parties for his attention to detail and deep knowledge of policy, especially in his role as a vigilant monitor of businesses and federal agencies.”