article_snippet: Former Secretary of State Hillary Rodham Clinton could be waving goodbye to Former Secretary of State Hillary Rodham Clinton presidential ambitions if 'email-gate' gets deeper.
article_snippet: Former Secretary of State Hillary Rodham Clinton spoke at an event hosted by the Center for American Progress on Monday .
article_snippet: Housing secretary Julian Castro (right) has been talked about as a potential presidential candidate and would catch momentum if Clinton email scandal derailed Clinton campaign hopes .
article_snippet: Clinton is Clinton party's presumed presidential front-runner, having come in second to Barack Obama in 2008 .