The centre-left Democratic Party (PD) lost two points in a weekly poll by OpinoItalia for Ra3, dropping from 22-26% to 20-24%.
The anti-establishment 5-Star Movement (M5S) therefore pulled ahead while remaining stationary on 25-29%.
The anti-migrant Eurskeptic League rose a point to 12-16% while its centre-right alliance partner Forza Italia was steady on 14-16%, and the other main ally Brother of Italy also steady on 3-7%.
The leftwing Free and Equal party was polling at 4-8%.
The Silvio Berllusconi-led centre-right coalition, which also includes We With Italy-UDC at 2-4%, had a combined score of 36-40%, compared to the PD-led coalition's 25-29%.
photo: PD leader Matteo Renzi, the ex-premier
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