Centre-left Sardinian governorship candidate Alessandra Todde has overtaken centre-right candidate Paolo Truzzu by 45.5% to 45.1% with 66.6% of the votes counted, after Todde caught up after being behind for much of the day.
Truzzu, 51, is a member of Premier Giorgia Meloni's rightwing Brothers of Italy (FdI) party and mayor of Cagliari while Todde, 54, is former deputy head of the leftwing populist 5-Star Movement (M5S) and former deputy industry minister under Mario Draghi.
Todde's lead looks set to grow further with the arrival of votes from the big cities like the capital Cagliari and Sassari where she has a healthy lead, while Truzzu is leading in smaller towns like Oristano and Olbia.
Going into the contest Truzzu led Todde by about five points in most opinion polls.
Tech magnate and former Democratic Party (PD) governor Renato Soru is currently third on 8.5% and the last, leftist and regionalist candidate, Lucia Chessa, has 0.9%.
The election is seen as a test of whether the 'broad field' alliance between the PD and the M5S can compete at a national level with the dominant rightwing alliance of FdI, the League and the post Berlusconi Forza Italia (FI) party.
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