Polls have closed in local elections being held across Italy for the first time since Romano Prodi's centre-left coalition won the April elections.
Exit polls look positive for Romano Prodi's centre-left
Exit polls, which correspondents say are not always reliable, suggest Mr Prodi's coalition has held Rome, Turin and Naples and run close in Milan.
Former PM Silvio Berlusconi campaigned for conservative mayors and warned of a backlash against the new government.
The governorship of Sicily is thought to have been held by the centre-right.
In all, voting took place in 1,200 cities and towns on Sunday and Monday.
Voting started on Sunday and continued in many areas on Monday. The interior ministry says turnout on Sunday was 35% in the municipal elections and 27.9% in provincial elections.
La Repubblica newspaper said the right was "seeking revenge for the legislative elections, the left is seeking a repeat".
Silvio Berlusconi campaigned on behalf of centre-right candidates
Mr Berlusconi still disputes the outcome of the general elections. He had been promising a strong showing from centre-right supporters in this weekend's vote.
The BBC's Christian Fraser, in Rome, says that if the first exit polls are any reflection, then he may be disappointed.
Mr Prodi insisted that the municipal elections "are not a test for the government because we have not yet started to govern".
The centre-left mayor of Rome, Walter Veltroni, credited with boosting the capital's cultural profile, is tipped to win a second term, according to exit polls.
He voted on Sunday in his pyjamas from his hospital room, where he is being treated for kidney stones.
In Sicily, partial returns showed the current centre-right governor, Salvatore Cuffaro, had won.
Mr Cuffaro, currently on trial charged with colluding with the Mafia, had faced a strong challenge from the centre-left candidate, Rita Borsellino. She is the sister of the late magistrate, Paolo, who was murdered by the Mafia in 1992.
In Naples, voting was marred by the arrest of five people who it is alleged were working for the Mafia.
They are accused of threatening candidates in municipal elections and charging them money to campaign in their neighbourhoods. Some candidates are already calling for another vote. Run-offs will be held in June in races where no-one has received 50%.
Our correspondent says that in the end, the results of these elections will probably reflect a country that is still politically divided.
Italy's new President, Georgio Napolitano, told a French magazine last week his country had never seen such a climate of confrontation. At times, he said, it verges on hatred.