As expected, highly visible Newark mayor Cory Booker will run in the October special election for the New Jersey Senate seat freed up by Frank Lautenberg’s passing last week. Booker made the announcement on Saturday morning, saying, “I’m here today because I know who we are, and what we are capable of. We all are the leaders who must now do more than ever to join in and fight, and lead the way forward.” And the knives are already out: The National Republican Senatorial Committee responded with a mass email questioning whether “Cory Booker the candidate can match Cory Booker’s celebrity persona … since campaigning is so much different from party hopping in Hollywood, appearing on television, or tweeting.” The candidate and the persona will likely be pitted against Democratic representatives Frank Pallone and Rush Holt in the August primary (both men are expected to announce their candidacies shortly.) If he wins, he might be faced with Republican Steve Lonegan (who has already announced his run) in the fall election. People Booker definitely won’t be running against: Jeffrey Chiesa and Chris Christie.