Biden tells donors: Keep me in mind for 2016

Biden, who started in the Senate young and would be just 70 in 2012, raised the possibility unprompted during a wide-ranging conversation at the May 19 dinner with major Democratic Party donors, a source in the room said. 

The Vice President, who has never ruled in or out running in six years, told the group he hadn't made up his mind, and cited both political conditions and his own health as relevant factors. 

But the spontaneous suggestion caught the attention of at least some in the audience, said the guest, "given he volunteered that without prompting...and given the audience."