But will the emergence of Rudy help or hurt Bloomberg, who has seen the campaign of overwhelmed and out-spent Democractic challenger Comptroller William Thompson recently come to life?
Over the past few years, Giuliani has leaned even more to the right, burnishing his national Republican credentials. While that endears him to upstate and national voters, it may not be a help among the city's overwhelmingly Democratic crowd who elected Giuliani on a fiscally conservative but socially liberal Republican-lite platform.
A failed Republican presidential candidate, Giuliani is also considering a run for governor. At his first mayoral debate versus Thompson on Tuesday, Bloomberg, who is running on both Republican and Independent Party lines, was booed when he said Giuliani would make a good governor.
However, there are still swaths of the city where Giuliani remains popular. As Election Day nears, Bloomberg is seeking to energize those voters.
President Obama is expected in town next week, so it's believed that Bloomberg is trying to bring out his own firepower in case the Commander-In-Chief gives a whole-hearted endorsement to Thompson -- as opposed to the weak endorsement of Thompson given by the president's spokesman last week.