Support for Italy's centre-left coalition is sharply up in the polls following the election of Florence Mayor Matteo Renzi as leader of the Democratic Party (PD), local media noted Saturday, according to dpa. "The centre-left overtakes the centre-right," the Corriere della Sera newspaper reported, while the Italian edition of the Huffington Post website spoke of a "Matteo Renzi effect" for the PD. Both reports cited a poll by the SWG institute showing the PD-led centre-left at 40.5 per cent, with support for Renzi's party up six points from the previous week, while conservatives led by former premier Silvio Berlusconi were trailing at 33.6 per cent. Earlier this week, Ixe pollsters had the centre-left on 33.6 per cent, with support for the PD up 2.1 points, against the centre-right's 33.1 per cent. A third poll by Datamedia had Renzi's forces prevailing over Berlusconi's by 34.4 to 33.6 per cent. Support for the anti-establishment Five Star Movement of satirist Beppe Grillo was down in all three surveys, ranging from 18.1 per cent to 21.9 per cent. Renzi belongs to the same party as Prime Minister Enrico Letta, who leads a grand coalition comprising the PD, centrists and renegade conservatives who have refused to follow Berlusconi's move to the opposition, but would still ally with him at the next elections. The Florence mayor harbours prime ministerial ambitions, but has pledged loyalty to the government for the time being. Berlusconi, who was ejected from parliament because of a tax fraud conviction, and Grillo, want to topple Letta and trigger early elections.