Despite Alemanno had repeatedly stated its intention to hold primary elections to choose the candidate of the centre-right coalition, on 2 September 2012 he announced his intention to run for a second term as Mayor of Rome. On the contrary, the centre-left coalition decided to hold the primary election on 7 April 2013 to decide its mayoral candidate. There were 6 main candidates: five from Democratic Party and one from Left Ecology Freedom. Among the most popular candidates there were Ignazio Marino, heart surgeon and senator, who was candidate in the 2009 Democratic Party leadership election; David Sassoli, journalist and MEP since 2009; and Paolo Gentiloni, former Minister of Communication in the Prodi II Cabinet. On 7 April Marino won the election and became the official candidate of the centre-left coalition.
The voting system is used for all mayoral elections in Italy, in the city with a population higher than 15,000 inhabitants. Under this system voters express a direct choice for the mayor or an indirect choice voting for the party of the candidate's coalition. If no candidate receives 50% of the votes, the top two candidates go to a second round after two weeks. This gives a result whereby the winning candidate may be able to claim majority support, although it is not guaranteed. For municipi the voting system is the same, not referred to the mayor but to the president of the municipio. The election of the City Council is based on a direct choice for the candidate with a preference vote: the candidate with the majority of the preferences is elected. The number of the seats for each party is determined proportionally.
Results
'''Summary of the 2013 Rome City Council election results ! colspan="4" rowspan="1" style="text-align:left;" | Parties and coalitions ! colspan="1" | Votes ! colspan="1" | % ! colspan="1" | Seats
''Municipi'' election
Reduced from 19 to 15 in March 2013, municipi are governed by a president and a council of four members who are elected by its residents every five years. The municipi frequently cross the boundaries of the traditional, non-administrative divisions of the city. In this election all 15 municipi were won by the center-left coalition, composed by Democratic Party and Left Ecology Freedom. Table below shows the results for each municipio with the percentage for each coalition on the first round:
Municipio
Centre-left
Centre-right
Elected President
Party
Municipio
Elected President
Party
XII
50.2
27.1
Cristina Maltese
PD
Table below shows the results for each municipio with the percentage for each coalition on the second round:
