Mark Kirk was born in Champaign, Ill., and now resides in the Chicago suburb of Highland Park. He earned a bachelor's at Cornell University, a master's at the London School of Economics and a law degree at Georgetown University.
Kirk has been all over the world. A Naval Reserve officer, he has served in Iraq, Haiti, Bosnia and Panama and done tours of duty at sea. Kirk has worked at the World Bank, at a top Chicago law firm and as an aide at the U.S. State Department. He also has been counsel to the U.S. House International Relations Committee.
Kirk was first elected to the U.S. House in 2000 when he won the open seat of his popular predecessor, Rep. John Porter. Kirk had been Porter's chief of staff years earlier.
He was elected to the U.S. Senate in 2010.
Kirk suffered a serious stroke early in 2012 and was out of the public eye for months afterward as he recovered.
He is divorced and has no children.
Mark Kirk took on a huge challenge when he ran in 2010 for the U.S. Senate seat once held by President Barack Obama. He won but soon found himself facing a challenge of a different kind — recovering from a major stroke.
Kirk suffered the stroke in January 2012. Part of his skull had to be removed to prevent damage to his swollen brain. He was hospitalized for more than two weeks before being transferred to a rehabilitation center, where he spent three months slowly building the strength to walk, climb stairs or simply get in and out of a car.
Doctors say Kirk will probably suffer permanent limits on motion with the left side of his body but will fully recover his mental abilities. Kirk kept out of sight during his recovery, but aides said he stayed on top of his official duties and Senate activity.
Kirk won the Senate seat by defeating Illinois Treasurer Alexi Giannoulias. He questioned Giannoulias' judgment by highlighting the failure of the Giannoulias family bank and its loans to some people with criminal backgrounds.
Kirk faced questions about his own judgment when it came to light that he had exaggerated or incorrectly described some of his service in the Navy Reserve. The most important issue was a claim that he had been named the reserves' intelligence officer of the year, when actually it was his entire unit that was recognized, not Kirk individually.
Kirk made the jump to the Senate after a long career in the House, where he belonged to the Tuesday Group, a caucus of moderate Republicans. During his tenure, Kirk emphasized legislation on suburban issues such as commuter rail and veterans' affairs.
While Kirk has been a moderate on issues like gun control and abortion, he did support prohibiting federal funding of abortions in the 2010 health care bill. He also twice voted against the approximately $800 billion economic stimulus packages in early 2009 that were designed to shake the country out of a recession.
Kirk angered conservative Republicans when he voted for cap-and-trade legislation meant to limit pollution that other Republicans say will kill jobs. Kirk now says he would vote against it in the Senate.
Committee Assignments: Appropriations; Banking, Housing, and Urban Affairs; Health, Education, Labor, and Pensions; Special Aging
American Conservative Union Rating: 60
Americans for Democratic Action Rating: 20
Mark Kirk is not up for re-election in 2014.
(Last updated by The Associated Press on June 5, 2014.)