WASHINGTON Michelle Obama and Cindy McCain share a dislike of rough-edged U.S. politics. Each tried to talk her spouse out of running for the White House.
Obama, wife of Democratic candidate Barack Obama, and McCain, who is married to Republican John McCain, are both known for an elegant sense of style, lending glamour to their husbands' campaigns.
McCain posed in size zero jeans for the latest issue of Vogue. Obama, who has also appeared in the fashion magazine, was praised by style writers for the violet sheath dress she wore to her husband's Democratic nomination victory rally and has been compared to former first lady Jacqueline Kennedy.
But the aspiring first ladies have plenty of differences.
Obama, 44, is a Princeton- and Harvard-educated lawyer raised by blue-collar parents on the working-class South Side of Chicago. She would be the first African American U.S. first lady.
Obama talks often on the campaign trail about being a working mother. Until recently, she juggled a job as a hospital executive with raising two young daughters and lending support to her 46-year-old husband's political aspirations.
The strong-minded Obama exudes confidence and is an accomplished public speaker. But her penchant for outspokenness has also drawn some criticism.
McCain, 54, the Arizona senator's second wife, is reserved and seems far less comfortable in the limelight when she campaigns with her husband, who is 18 years her senior.
The blond, blue-eyed McCain is a former rodeo queen and cheerleader who holds a master's degree in special education from the University of Southern California. She grew up in a wealthy family in Phoenix and is heiress to Hensley & Co, one of the largest U.S. distributors for brewing giant Anheuser-Busch.
Last month, she released a tax return showing she made about $6 million in 2006.
McCain has raised four children, including a daughter Bridget, 16, whom she adopted from Mother Teresa's orphanage in Bangladesh. McCain has traveled the globe as part of her charitable work.
McCain's deferential manner puts her in the company of more traditional first ladies such as Nancy Reagan and Laura Bush.
"She is more in the classic mold of the candidate's wife on the campaign trail," said Calvin Jillson, a political scientist at Southern Methodist University in Dallas.
He said McCain has her own version of the "Nancy Reagan stare," the adoring gaze that the former first lady perfected.
"If you look at Michelle Obama, it appears that throughout their married life, she and her husband have been very much equals," Jillson said. Her image as an equal partner was on display with the celebratory fist-bump the Obamas shared on the night he clinched the nomination last week.
America has had nontraditional first ladies before. They included Rosalynn Carter, wife of Jimmy Carter who sat in on Cabinet meetings, and Hillary Clinton, who was named by her husband to lead a health-care task force.
Obama met her husband through her work as a corporate lawyer and is his closest adviser, although associates have described her role as less of a policy-oriented one than that of a confidante who provides a reality check.
She has acquired an image as a tough-minded task-master.
In a favorite line on the campaign trail, the Illinois senator says his wife often reminds him that he's "not a perfect man."
When asked about his flaws during one campaign stop, Obama advised the questioner to "talk to my wife."
"She will have a pretty long list," he said, starting with his failure to hang up his clothes properly.
But some pundits have put some of Obama's criticism of her husband -- that he snores and leaves socks on the floor -- in the category of "too much information."
In one comment seized upon by conservative Internet bloggers, Michelle Obama remarked, "For the first time in my adult life, I am proud of my country."
That led critics to accuse her of being unpatriotic, saying that her comment made it appear she had not been proud of her country before her husband ran for president.
A day later, Cindy McCain told a campaign rally, "I am proud of my country. I don't know about you, if you heard those words earlier -- I am very proud of my country."
But she too has drawn criticism. When she refused to release her tax returns critics said her lack of transparency was at odds with her husband's message of openness in government. McCain eventually relented.
She has also talked openly about her addiction in the early 1990s to painkillers, originally prescribed for back pain, which she at first kept secret from her husband and family.
McCain has also made a full recovery from a stroke that nearly killed her four years ago.
Both women serve a crucial role of giving emotional support to their spouses amid the grueling slog of the campaign. Barack Obama's mood brightens visibly when his wife joins him on the campaign trail. McCain has a similar effect on her husband.
(Additional reporting by Tim Gaynor; editing by Patricia Zengerle)