Born Jean Anne Carpenter in Washington, D.C. to a working-class family, she was determined to go to college. She worked through the year while attending George Washington University. She graduated in 1955 with a degree in Business and Public Administration, the first in her family to graduate from high school and college. She is an alumna of Kappa Delta sorority.
She married Mel Carnahan in 1954. As her husband entered politics, she became his political partner. He was elected Governor of Missouri, serving 1993–2000. She was an activist First Lady: an advocate for on-site day care centers for working families, childhood immunization, abuse centers, the arts, and Habitat for Humanity.
In 2000, Governor Carnahan ran for a Senate seat from Missouri against incumbent Republican John Ashcroft. Three weeks before election day, the governor was killed in an airplane crash, along with their son Randy (who piloted the plane) and Chris Sifford, the governor's chief of staff and campaign advisor). Due to the short amount of time before the election, Missouri election law did not allow his name to be removed from the ballot. Acting Governor Roger Wilson announced that he would appoint Jean Carnahan if her husband were to posthumously win the election, making her effectively the Democratic candidate by proxy.
Out of respect, Ashcroft suspended his campaign during the mourning period for the governor. Jean Carnahan did not actively campaign but announced that she intended to accept Wilson's appointment; she filmed one campaign commercial.
The race had been close before the accident, and Mel Carnahan posthumously won (51-48%), receiving 1.19 million votes out of 2.36 million cast. Jean Carnahan was appointed to the Senate in 2001, but under Missouri law, she would serve only until a special election could be held.
Ashcroft was subsequently nominated by President George W. Bush to be US attorney general, and because cabinet appointments are subject to Senate approval, Carnahan found herself in the unusual position of casting a vote against the nomination of her de facto opponent.
In 2002, the special election was held for the remainder of the six-year term. Carnahan ran, but was defeated in a close race by Republican James Talent; the margin was only 22,000 votes (49.8–48.6%).
In 2004 her son Russ Carnahan, was elected to Congress and her daughter Robin Carnahan was elected Missouri's Secretary of State. Robin's bid to follow her mother as a United States Senator failed, however, when she was defeated by Republican U.S. Representative Roy Blunt in the 2010 election to succeed Missouri's senior Senator, Republican Kit Bond. Russ Carnahan lost his House seat in the 2012 elections after his district was eliminated, forcing him to run in the Democratic primary against fellow incumbent William Lacy Clay, Jr., whose district encompassing inner city St. Louis was kept largely intact.
Since losing her Senate race, Jean Carnahan has continued as an activist and author. She has written four books and numerous opinion pieces.
She is among the former Missouri First Ladies who have participated in the cherry blossom tree planting in Marshfield, Missouri.2000 race for U.S. Senate
Mel Carnahan (D), 51% (posthumously elected; Jean Carnahan appointed to fill seat)
John Ashcroft (R) (inc.), 48%
2002 race for U.S. Senate (special election to fill remainder of term)
Jim Talent (R), 50%
Jean Carnahan (D) (inc.), 49%
(1998) If Walls Could Talk: The Story of Missouri’s First Families. MMPI ISBN 0-9668992-0-2.
(1999) Christmas at the Mansion. MMPI ISBN 0-9668992-1-0.
(2000) Will You Say a Few Words?. Walsworth Publishing Co. ISBN 0-8262-1513-0.
(2004) Don’t Let the Fire Go Out!. University of Missouri Press. ISBN 0-8262-1513-0.
(2009) The Tide Always Comes Back. Skyhorse Publishing ISBN 1-60239-744-9.
(2012) A Little Help from My Friends...and Other Hilarious Tales of Graying Graciously. Vantage Point Books ISBN 1-936467-23-2.