From Politico

There may be a reason other than security that the campaign doesn't want Signator talking to the press.

During Obama's 2004 Senate race, in the weeks after Obama's convention speech had marked him as a rising star, Signator accompanied Obama to an African-American parade in Chicago. According to an Obama biography by Chicago Tribune veteran David Mendell, the crowd chanted "O-ba-ma! O-ba-ma! O-ba-ma!" and gave the young candidate such a passionate reception that Signator, identified by Mendell as Obama's "driver and bodyguard," joked that he "thought Barack was going to rise up over the people and start saying, 'My children, my children, I have come to free you"