Michelle Obama and Cindy McCain appear as different as black and white, but both women have multiple higher-education degrees, their own career accomplishments, and have taken bold roles in their husbands' presidential campaigns.
One of these two women will succeed Laura Bush, a former librarian who gave up her career to be a stay-at-home mom and later a quiet presence in the White House.
"Americans are going to get a different first lady," said Melissa Harris-Lacewell, associate professor of politics and African-American studies at Princeton University, and who is friends with Michelle Obama. "Whoever winds up there, it's going to be a different approach."
And both may owe a debt to Hillary Clinton in allowing them to be a more independent and assertive first lady.
In the 1992 presidential campaign, Clinton was lambasted for being such a strong personality that Bill Clinton said voters would get "two for one." Hillary Clinton again became a public pinata for unsuccessfully pushing her health care agenda through Congress.
"The campaigns don't necessarily want the wives to appear overly substantive," said Carl Sferrazza Anthony, a historian for the National First Ladies Library in Canton, Ohio. "The campaign of 1992 stands out as a stark reminder of how a first lady can be demonized if there is the slightest suggestion she might use her intelligence and experience and offer advice to her husband."
But Americans are now ready for a more dynamic first lady, according to Kim Gandy, president of the National Organization for Women.
"There's been a generational shift," Gandy told ABCNews.com. "The reception that Hillary got as an accomplished lawyer in 1992 was far more threatening than either Cindy McCain or Michelle Obama will get in 2008."
Michelle opened the Democrats' convention in Denver last week and Cindy was a stand-in for her husband at the GOP's Twin Cities convention this week.
Michelle Obama would clearly be the history maker, being the first black woman to head the East Wing of the White House, and that would bring added pressures that could temper her behavior.
"The twist is that Cindy McCain has more of an opportunity to make a more radical difference," said Catherine Algore, visiting professor at Claremont McKenna College and author of "A Perfect Union: Dolley Madison and the Creation of the American Nation."
"It's the paradox of her being a Republican woman, with traditional appearance and presence of self. She can actually do more than someone looked at as a radical, liberal feminist and black woman," Algore told ABCNews.com.
"In some ways Michelle Obama is constrained by our own prejudices and expectations, whereas Cindy McCain can take that conservative, former beauty queen wife and mother and philanthropist and run with it," she said.
But either women will have to negotiate her high-powered ego through White House traditions.
History demonstrates that the role of first lady is complex, according to Edward Berkowitz, professor of history and public policy at George Washington University.
"There are contradictions built in to the family and political roles," he told ABCNews.com. "How to reconcile between being active and not getting involved, giving the president the proper space, the proper environment for giving advice, but not definitive advice. The tensions are very hard to navigate."