Since the US Supreme Court overturned Roe v. Wade, Vice President Kamala Harris has become the administration's most visible advocate of abortion rights.SAUL LOEB/AFP via Getty ImagesKamala Harris' allies are frustrated with chatter about potential Biden replacements, Politico reported.The allies feel that Gavin Newsom and Gretchen Whitmer are being mentioned more than the VP.Harris has stood firmly behind Biden and defended the administration's record following his debate.After President Joe Biden's widely panned debate performance against former President Donald Trump, Vice President Kamala Harris emerged as perhaps the president's most forceful advocate.Harris, who has enjoyed a strong governing relationship with Biden, is seen by many as a top successor to the president should he exit the presidential race.But some of Harris' allies are frustrated that Democratic figures like California Gov.