Mrs Kirchner began to gyrate to the rhythms of a politically-themed song on Monday at the end of a rally of ruling party candidate Daniel Scioli, the chosen successor of Mrs Fernandez.
Mr Scioli, who is the governor of Buenos Aires, could be seen standing next to an arm-swaying Mrs Kirchner.
The dance lasted several minutes, and Mrs Kirchner made an open finger salute to the large crowd in attendance, a gesture that is synonymous to the 'Kirchnerista' political movement.