McCloskey, who represented southwestern Indiana's 8th District in Congress from 1983 to 1995, died at his Bloomington home Sunday afternoon with relatives and friends at his bedside, said Dan Combs, chairman of the Monroe County Democratic Party.
He had been released from a Bloomington hospital Oct. 28 after an 11-day stay as his health worsened.
"Frank always wanted to do good," Combs said. "I honestly wouldn't say that he was a good politician. He wasn't tricky, slick or deceitful. He fought for things he thought were right. If something sounded good that's what he did."
Combs said McCloskey's interest in the Balkans began in the early 1990s as the former Yugoslavia disintegrated and violence escalated in the region.
"There's almost no benefit for a politician from southern Indiana becoming involved in the affairs of the Balkans, but he did it because he thought he could help those people," Combs said.
McCloskey, who made several trips to Bosnia during his years in Congress, called in 1992 for selective air strikes against Serb forces if they continued their siege of Bosnia-Herzegovina.
He later criticized the Clinton administration's handling of the Bosnian conflict, and called for the resignation of then-Secretary of State Warren Christopher, warning that Serbs were committing genocide in Bosnia.
McCloskey also called for war crime trials for Serb leaders, specifically Serbian President Slobodan Milosevic, who was ousted in 2000 and is currently on trial in The Hague, Netherlands.
Born in Philadelphia in 1939, McCloskey went to high school in Norristown, Pa., and entered the Air Force immediately after graduation. He served until 1961 before coming to Indiana University in Bloomington.
McCloskey worked as a reporter for The Indianapolis Star, the Herald-Telephone in Bloomington and the City News Bureau in Chicago before graduating from IU in 1968 with a bachelor of arts.
He was elected mayor of Bloomington in 1972, a year after he graduated from law school at IU.
McCloskey served as mayor for 10 years before being elected to Congress in 1982. He won re-election by just four votes two years later after five recounts in a race against Republican Rick McIntyre. He lost in the 1994 race that swept Republicans back into power in Congress.
In 2002, McCloskey was named director of Kosovo programs for the National Democratic Institute for International Affairs, where he was teaching leaders how to govern democratically.
Combs said McCloskey had been on the job only a few weeks in that post when he fell ill last year.
McCloskey is survived by his wife of more than 30 years, Roberta, and their two adult children. Funeral arrangements are pending.