FACTBOX: Possible Democratic VP candidates

(Reuters) - Democratic presidential candidate Barack Obama has chosen a vice presidential running mate but has not yet revealed the name.

Here is a list of some possible picks:

* Evan Bayh, 52 - The Indiana senator supported Hillary Clinton during the nomination battle. He has been vocal on national security issues in the Senate as a member of the Armed Services and Intelligence Committees. Bayh, who served two terms as Indiana's governor, is said to have an even temperament that might be a good fit with Obama's.

* Joseph Biden, 65 - The senator from Delaware, chairman of the Senate Foreign Relations Committee, who would give Obama authority on foreign policy. But Obama might not want a second senator on the ticket, and could be looking for a fresher face to reinforce his message that this election is about change.

* Hillary Clinton, 60 - Polls have shown strong Democratic support for a "dream team" ticket of Obama, the first black to lead a major-party presidential ticket, and Clinton, who sought to become the first woman to win the White House. Obama has not ruled out the option, which would help unify the party after a long nominating battle. But the New York senator and former first lady also would bring complications, including the role of former President Bill Clinton. A joint ticket could help attract some Clinton supporters, notably white working-class voters, who have balked at backing Obama.

* Chris Dodd, 64 - The Connecticut senator, a fluent Spanish speaker and expert in Latin American issues, chairs the Senate Banking Committee and is a former presidential candidate who quickly endorsed Obama after dropping out. He would bolster Obama's foreign policy and economic credentials, but presents many of the same drawbacks as Biden.

* Chuck Hagel, 61 - The Republican senator from Nebraska, a conservative Vietnam veteran but outspoken critic of the Iraq war, would help Obama reach out to independents and Republicans and reinforce his promise to bridge partisan divides.

* Tim Kaine, 50 - The Virginia governor was an early and strong Obama supporters and could help him in a state that has been Republican in presidential elections but has been turning Democratic in recent years.

* Sam Nunn, 69 - The former Senate Armed Services Committee chairman from Georgia is a respected foreign and military policy voice, but his age and conservative views on some social issues might make him an awkward fit.

* Bill Richardson, 60 - The New Mexico governor, a Hispanic, could help with Latinos -- the fastest-growing segment of the electorate and a potentially vital voting bloc. A seasoned negotiator, the former energy secretary, congressman and U.N. ambassador would also bring foreign policy experience and inside knowledge of how Washington works.

* Kathleen Sebelius, 60 - The two-term Kansas governor could bring some vital elements: she's a woman and as leader of a mostly Republican state has shown she can work across party lines. But she is largely untested nationally.

(Reporting by Deborah Charles; editing by David Wiessler and Mohammad Zargham)