-LRB- CNN -RRB- -- A big part of being president is making decisions , and one of the key decisions a would-be president can make is who he or she marries . Cindy McCain has a master 's degree in special education . She is part owner of her father 's business . It 's not like deciding whether to press the nuclear button , but first ladies in the United States can wield enormous influence in politics and in society . They 're not elected . They 're not paid . There 's no precise job description . But whether it 's an elegantly dressed Jacqueline Kennedy giving Americans a tour of the White House , Eleanor Roosevelt speaking on civil rights or Hillary Clinton saying `` I suppose I could have stayed home and baked cookies , '' first ladies are praised , criticized , adored and scorned -- but never ignored . The two women poised for the job , 54-year-old Cindy McCain , wife of Republican Sen. John McCain , and 44-year-old Michelle Obama , wife of Democratic Sen. Barack Obama , come from strikingly different backgrounds . Watch the different styles of potential first ladies '' McCain is the only child of a wealthy Arizona businessman , James Hensley , founder of Hensley & Co. , a major distributor of Budweiser beer . Her stake in the business is estimated to be at least $ 100 million . She refused to release her full tax returns , saying `` I am not the candidate , '' but later provided summary pages of her 2006 taxes without details . Cindy McCain has a master 's degree in special education . She met John McCain in 1979 when he was the U.S. Navy 's liaison to the Senate . He was 18 years older than she . He divorced his wife and married Cindy in 1980 . The McCains have four children , including a daughter adopted from an orphanage in Bangladesh . A tall , striking blonde with blue eyes , Cindy McCain has had health issues including a near-fatal stroke in 2004 and a battle with prescription drugs that she says is behind her . In an interview with CNN , McCain said her priority in life is charity . `` I 've been internationally involved in many , many things , '' she said . `` Land mine removal , children 's health care , poverty around the world -- and I will continue that . '' On the campaign trail , always dressed impeccably , she stays `` on message '' but did take a swipe at Michelle Obama after her statement , `` For the first time in my adult lifetime , I 'm really proud of my country . '' `` I do n't know about you , '' McCain said in February , '' ... I 'm very proud of my country . '' Michelle Obama has a blunt style and a wry , quirky sense of humor that goes over well with supporters . She does n't mince words . In an interview with CNN , she said , `` I think race is always -- still , in this country , it 's always on the table . '' Michelle Obama was raised in a working-class family in Chicago , Illinois , but educated at some of America 's elite universities : Princeton and Harvard Law School . She was hired by a top-flight law firm in Chicago and met Barack Obama when she was assigned to mentor him . They married in 1992 and have two young daughters . Michelle Obama cuts an impressive figure -- tall , slim and dressed in Jackie-Kennedy-like sheath dresses . If her husband is elected , she will make history as the first African-American first lady . She has given insights into her husband 's domestic behavior : He does n't pick up his socks . Cindy McCain praises her husband as a fighter who wo n't give up . Will we learn more of substance ? Their husbands offer starkly different views of what they would do in office and Americans often look to their first ladies as a window into the thinking of the president . We 're all ears .