Rawlings-Blake appears in the nearly one-minute commercial urging voters to do what's "right and fair."
"To do nothing is to look a child in the eye and destroy their possibilities," the mayor says in the commercial.
McDonough, a Middle River Republican, said Rawlings-Blake's appeal to voters comes at the expense of other students.
"I think what she's doing is destroying the dreams of young, black city kids," McDonough said. "Maybe it's someone who might be the first person in their family to go to college until they apply and find out that the position is filled by someone who is here illegally."
The kerfuffle over the commercial is round three in an on-going flap between McDonough and Rawlings-Blake.
McDonough has twice criticized the mayor for issues related to what he called "" that he said were causing problems in the Inner Harbor area
In May, Rawlings-Blake criticized McDonough directly for his support of the so-called "Doomsday state budget."
McDonough said he expects his comments will draw more of the same.
"I'm fighting for the black community," McDonough said. "This will stimulate debate. This will get people talking. This will make the heads of the editors at The [Baltimore] Sun explode. I will be called a racist. Danny Rodricks will write another story that no one will understand."