Ben Carson Retired Physician
Age on Election Day: 65
Religion: Seventh-day Adventist
Base: Evangelicals
Résumé: Famous pediatric neurosurgeon, youngest person to head a major Johns Hopkins Hospital division. Founder of the Carson Scholars Fund, which awards scholarships to children of good character.
Education: B.A. Yale University. M.D. University of Michigan Medical School.
Family: Married to Candy Carson (1975), with three adult sons. The Carsons live in Maryland with Ben's elderly mother Sonya, who was a seminal influence on his life and development.
Claim to fame: Carson spoke at a National Prayer Breakfast in 2013, railing against political correctness and condemned Obamacare – with President Obama sitting just a few feet away.
Achilles heel: Carson is inflexibly conservative, opposing gay marriage and once saying gay attachments formed in prison provided evidence that sexual orientation is a choice.
Ted Cruz Texas senator
Age on Election Day: 45
Religion: Southern Baptist
Base: Tea partiers
Résumé:U.S. senator. Former Texas solicitor general. Former U.S. Supreme Court clerk. Former associate deputy attorney general under President George W. Bush.
Education: B.A. Princeton University. J.D. Harvard Law School.
Family: Married to Heidi Nelson Cruz (2001), with two young daughters. His father is a preacher and he has two half-sisters.
Claim to fame: Cruz spoke on the Senate floor for more than 21 hours in September 2013 to protest the inclusion of funding for Obamacare in a federal budget bill. (The bill moved forward as written.) He has called for the complete repeal of the medical insurance overhaul law, and also for a dismantling of the Internal Revenue Service. Cruz is also outspoken about border security.
Achilles heel: Cruz's father Rafael, a Texas preacher, is a tea party firebrand who has said gay marriage is a government conspiracy and called President Barack Obama a Marxist who should 'go back to Kenya.' Cruz himself also has a reputation as a take-no-prisoners Christian evangelical, which might play well in South Carolina but won't win him points in the other early primary states and could cost him momentum if he should be the GOP's presidential nominee.
Jim Gilmore Former Virginia governor
Age on Election Day: 67
Religion: United Methodist
Base: Conservatives
Résumé: Former governor and attorney general of Virginia. Former chairman of the Republican National Committee. Former U.S. Army intelligence agent. President and CEO of the Free Congress Foundation. Board member of the National Rifle Association
Education: B.A. University of Virginia.
Family: Married to Roxane Gatling Gilmore (1977), with two adult children. Mrs. GIlmore is a survivor of Hodgkin's lymphoma
Claim to fame: Gilmore presided over Virginia when the 9/11 terrorists struck in 1991, guiding the state through a difficult economic downturn after one of the hijacked airliners crashed into the Pentagon. He is nest known in Virginia for eliminating most of a much-maligned personal property tax on automobiles, working with a Democratic-controlled state legislature to get it passed and enacted.
Achilles heel: Gilmore is the only GOP or Democratic candidate for president who has been the chairman of his political party, giving him a rap as an 'establishment' candidate. A social-conservative crusader, he is loathed by the left for championing the state law that established 24-hour waiting periods for abortions. Gilmore also has a reputation as an indecisive campaigner, having dropped out of the 2008 presidential race in July 2007.
Mike Huckabee Former Arkansas governor
Age on Election Day: 61
Religion: Southern Baptist
Base: Evangelicals
Résumé: Former governor and lieutenant governor of Arkansas. Former Fox News Channel host. Ordained minister and author.
Education: B.A. Ouachita Baptist University. Southwestern Baptist Theological Seminary (did not finish).
Family: Married to Janet Huckabee (1974), with three adult children. Mrs. Huckabee is a survivor of spinal cancer.
Claim to fame: 'Huck' is a political veteran and has run for president before, winning the Iowa Caucuses in 2008 and finishing second for the GOP nomination behind John McCain. He's known as an affable Christian and succeeded in building a huge following on his weekend television program, in which he frequently sat in on the electric bass with country & western groups and other 'wholesome' musical entertainers.
Achilles heel: Huckabee may have a problem with female voters. He complained in 2014 about Obamacare's mandatory contraception coverage, saying Democrats want women to 'believe that they are helpless without Uncle Sugar.' He earned more scorn for hawking herbal supplements in early-2015 infomercials as a diabetes cure, something he has yet to disavow despite disagreement from medical experts.
John Kasich Ohio governor
Age on Election Day: 64
Religion: Anglican
Base: Centrists
Résumé: Governor of New York. Former chairman of the U.S. House Budget Committee. Former Ohio congressman. Former Ohio state senator.
Education: B.A. The Ohio State University.
Family: Married to Karen Waldbillig (1997). Divorced from Mary Lee Griffith (1975-1980).
Claim to fame: Kasich was Ohio youngest-ever member of the state legislature at age 25. He's known for a compassionate and working-class sensibility that appeals to both ends of the political spectrum. In the 1990s when Newt Gingrich led a Republican revolution that took over Congress, Kasich became the chairman of the House Budget Committee – a position for a wonk's wonk who understands the nuanced intricacies of how government runs.
Achilles heel: Some of Kasich's political positions rankle conservatives, including his choice to expand Ohio's Medicare system under the Obamacare law, and his support for the much-derided 'Common Core' education standards program.
Rand Paul Kentucky senator
Age on Election Day: 53
Religion: Presbyterian
Base: Libertarians
Résumé: US senator. Board-certified ophthalmologist. Former congressional campaign manager for his father Ron Paul.
Education: Baylor University (did not finish). M.D. Duke University School of Medicine.
Family: Married to Kelley Ashby (1990), with three sons. His father is a former Texas congressman who ran for president three times but never got close to grabbing the brass ring.
Claim to fame: Paul embraces positions that are at odds with most in the GOP, including an anti-interventionist foreign policy, reduced military spending, criminal drug sentencing reform for African-Americans and strict limits on government electronic surveillance – including a clampdown on the National Security Agency.
Achilles heel: Paul's politics are aligned with those of his father, whom mainstream GOPers saw as kooky. Both Pauls have advocated for a brand of libertarianism that forces government to stop domestic surveillance programs and limits foreign military interventions.
Rick Santorum Former Penn. senator
Age on Election Day: 58
Religion: Catholic
Base: Evangelicals
Résumé: Former US senator and former member of the House of Representatives from Pennsylvania. Former lobbyist who represented World Wrestling Entertainment.
Education: B.A. Penn State University. M.B.A. University of Pittsburgh. J.D. Penn State University Dickinson School of Law.
Family: Married to Karen Santorum (1990), with seven living children. One baby was stillborn in 1996. Another, named Isabella, is a special needs child with a genetic disorder.
Claim to fame: Santorum won the 2012 Republican Iowa Caucuses by a nose. He won by visiting all of Iowa's 99 states in a pickup truck belonging to his state campaign director, a consultant who now worls for Donald Trump.
Achilles heel: As a young lobbyist, Santorum persuaded the federal government to exempt pro wrestling from regulations governing the use of anabolic steroids. And the stridently conservative politician has attracted strong opposition from gay rights groups. One gay columnist held a contest to redefine his name, buying the 'santorum.com' domain to advertise the winning entry – which is too vulgar to print.
Scott Walker Wisconsin governor
Age on Election Day: 49
Religion: Christian (nondenominational)
Base: Conservative activists
Résumé: Governor of Wisconsin. Former Milwaukee County Executive. Former member of the Wisconsin State Assembly.
Education: Marquette University (did not finish)
Family: Married to Tonette Tarantino (1993), with two children. One of Mrs. Walker's cousins is openly lesbian and was married in 2014, with the Walkers attending the reception.
Claim to fame: Walker built his national fame on the twin planks of turning his state's past budget shortfalls into surpluses and beating back a labor-union-led drive to force him out of office through a recall election. Both results have broad appeal in the GOP.
Achilles heel: Wisconsin has suffered from a shaky economy during Walker's tenure, which makes him look weak compared with other governors who presided over more robust job-creation numbers. He promised to create 250,000 private sector jobs but delivered less than 60 per cent of them. Also, he led an effort in the state legislature to enact $800 million in tax cuts – putting the Badger State back on the road to government deficits.