Five current senators are running for president in 2016. Along with a number of former governors, the field includes two candidates with medical degrees, one former tech CEO and a billionaire real estate mogul/TV host.
Here's a look at the major candidates who have declared that they're in the race for the Democratic or Republican presidential nomination.
Lincoln Chafee: Chafee has been a Democrat, an independent and a Republican during his political career. And he's the only candidate with experience as a blacksmith on his résumé. Chafee fact sheet Hillary Rodham Clinton: Clinton is a former secretary of State, senator and first lady, and has said she would be "the youngest woman president in the history of the United States." Clinton fact sheet Martin O'Malley: The longtime Maryland politician got his start as a field director for former Democratic presidential candidate Gary Hart. As governor, O'Malley repealed the death penalty and legalized same-sex marriage. O'Malley fact sheet Bernard Sanders: A Brooklyn-born writer and carpenter, Sanders won his first election for mayor of Burlington, Vt., by just 10 votes. He became the first self-identified socialist in Congress since the 1920s when he was elected to the House in 1990. Sanders fact sheet Republicans Jeb Bush: Bush is the first brother of a former president to seek the office himself since Sen. Edward M. Kennedy challenged President Jimmy Carter for the Democratic nomination in 1980. The former governor of Florida has also worked in the financial sector, including as a banker in Caracas, Venezuela. Bush fact sheet Ben Carson: The Detroit native, who has served as a Fox News commentator, gained prominence as a pediatric neurosurgeon, and was the first surgeon to successfully separate a pair of twins joined at the head. Carson fact sheet
Chris Christie: The Garden State governor is famous for his in-your-face style and his epic battles with teachers' unions in New Jersey made him a conservative hero. He was critical of members of the House for delaying recovery funds for his state in the wake of Superstorm Sandy. Christie fact sheet
Ted Cruz: As an undergraduate at Princeton University, Cruz won an award for speaker of the year as a member of the debate team. Before serving in the Senate, he was the first-ever Hispanic clerk for the chief justice of the United States. Cruz fact sheet Carly Fiorina: When Fiorina was chosen to lead Hewlett-Packard in 1999, she became the first woman to be hired to run a Fortune 50 company. Her dismissal in 2005 made her the first woman to be fired from such a job. Fiorina fact sheet Jim Gilmore: The former Virginia governor served for a year as head of the Republican National Committee but left in 2002 after the GOP lost governors' elections in New Jersey and Virginia and reportedly after tensions with Republican strategist Karl Rove. Gilmore fact sheet Lindsey Graham: The South Carolina senator is the son of a tavern owner and an outspoken hawk. On his status as a bachelor, Graham suggested that as president he would institute "a rotating first lady." Graham fact sheet Mike Huckabee: While serving as governor of Arkansas, Huckabee played bass in a classic rock cover band with staff members called "Capitol Offense." After being warned he might die from diabetes, he lost 100 pounds and wrote a book called "Quit Digging Your Grave With a Knife and Fork." Huckabee fact sheet
Bobby Jindal: A former Rhodes scholar, Jindal got off to an early start in government, running Louisiana's Department of Health and Hospitals at age 24. The Louisiana governor urged fellow Republicans to "stop being the stupid party" in the wake of self-inflicted wounds during the 2012 election cycle. Jindal fact sheet
John R. Kasich: The second-term governor of Ohio and and former congressman of 18 years also worked at Lehman Brothers investment bank. Kasich's record includes voting against a ban on assault weapons as a member of the House in 1994, and signing tax cuts and a Medicaid expansion as governor. Kasich fact sheet George Pataki: Pataki has said he sees himself as following in the footsteps of Teddy Roosevelt in "enhancing the outdoors," and environmentalists have praised his record as governor of New York, including the preservation of nearly a million acres of open space. Pataki fact sheet Rand Paul: As a 13-year-old, Paul attended the 1976 Republican convention with his father, former Rep. Ron Paul, who headed Ronald Reagan's Texas delegation. The Kentucky senator is also an ophthalmologist with a medical degree from Duke. Paul fact sheet Marco Rubio: When Rubio first ran for city commissioner in West Miami in 1998, Jeb Bush wrote his campaign a $50 check. The son of Cuban exiles was part of the 2013 bipartisan "gang of eight" senators who wrote a sweeping overhaul of immigration law. Rubio fact sheet Rick Santorum: The former senator from Pennsylvania came so close to beating Mitt Romney in the 2012 Iowa caucuses that he was announced as the winner. Santorum joined forces with Clinton and other senators to request federal funds to research how electronic media affect children's development. Santorum fact sheet Donald Trump: "The Donald" runs a real estate empire that includes numerous office towers and resorts, and his holding company is also part owner of several beauty pageant franchises including Miss Universe. In the political realm, he takes credit for forcing President Barack Obama to release his long-form birth certificate. Trump fact sheet
Rick Perry suspended his campaign on Sept. 11, 2015: Perry is a former Air Force pilot who was the longest-serving governor in Texas history. After his bid for the GOP presidential nomination in 2012 was doomed by a series of gaffes, he told CNBC that he had been "a little arrogant." Perry fact sheet Scott Walker suspended his campaign on Sept. 21, 2015: The Wisconsin governor has won every election he has run in since his 1993 campaign for state assembly, including a recall election in his first term as governor in 2012. The son of a minister and a part-time secretary, Walker's anti-union politics have made him a conservative hero. Walker fact sheet Jim Webb suspended his campaign on Oct. 20, 2015: The Naval Academy grad is a Vietnam War vet who served in the Senate and as an assistant secretary of defense, and was secretary of the Navy under President Ronald Reagan. He won an Emmy for covering the Marines in Beirut, Lebanon, for PBS and has written 10 books. Webb fact sheet -- Compiled by the CQ staff
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