Even if Bill and Hillary end up switching roles, their collaborative habits are deeply rooted, and their years in the White House offer strong clues as to how they would conduct themselves if they returned to 1600 Pennsylvania Avenue.

It's well known that

Laura Bush

single-handedly persuaded her husband, George W. Bush, to lay off the bottle when he was in his early 40s. By being an emotional rock when her husband needed it the most, Laura helped Bush get back on his feet.

Thanks to Laura's emotional strength, Bush went on to become the Governor of Texas and the President of the United States. Polled as one of the most popular first ladies, Laura Bush is involved in topics of both national and global concern.

She has continued to advance her trademark interests of education and literacy by establishing the annual National Book Festival in 2001 and encouraging education on a worldwide scale.

She has also advanced the causes of women through The Heart Truth and Susan G. Komen for the Cure. She serves as a representative of the United States during her trips abroad, which tend to focus on HIV/AIDS and malaria awareness.

Jacqueline Kennedy

It was Jacqueline who updated the White House and turned it into a showcase for design, fashion and art, while her husband, John F. Kennedy, tackled the political crisis of the early '60s.

In a column for New York's The City Review, Michele Leight writes of Jacqueline, "Her impact on American culture was significant.

She took America out of the staid and conservative 1950s and into the world of classy international elegance and also became an important champion of the arts and historic preservation."

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