ROME: Italians began voting Sunday in regional elections seen as a referendum on embattled Prime Minister Silvio Berlusconi two years into his mandate.

Pollsters predict gains for Berlusconi's troublesome coalition partner, the anti-immigration Northern League, and a low turnout reflecting voters' disenchantment with the political class after an exceptionally negative campaign.

Some 41 million Italians are eligible to vote in the elections for governors of 13 of the country's 20 regions.

Berlusconi, flagging in opinion surveys and beset by scandal, has campaigned hard to get people out to vote for his centre-right People of Freedom (PDL) party for the last electoral test before his term ends in 2013.

If the populist Northern League makes major gains in the wealthy regions of Lombardy and Veneto, it is likely to demand a new cabinet post and city hall in Berlusconi's native Milan, Italy's industrial capital.

The party was an essential ally in Berlusconi's return to power for a third time in 2008, campaigning on pledges of cracking down on illegal immigration and crime, often linking the two.

The centre-right is reeling from the arrests in February of party members accused of accepting kickbacks.

That scandal was quickly followed by embarrassment when the PDL fumbled over its candidate lists in Rome's Lazio region and Berlusconi's native Lombardy.

And earlier this month prosecutors opened a probe into allegations that Berlusconi, 73, tried to gag a political talk show that is often critical of him.

Berlusconi, who campaigned for the PDL on the slogan "Love Always Wins Over Envy and Hatred", has seen his approval rating slip to 44 percent, while the PDL-Northern League government scored only 38 percent in a recent opinion poll.

The Ipsos polling institute predicted a low turnout because of concern about employment and the perception that the government has done little to address the financial crisis.

A recent study found that one in four Italians have no interest in politics.

Berlusconi has already lowered expectations, experts said, noting that the flamboyant media tycoon initially predicted six wins for the centre-right against seven for the centre-left, but now would be content with victories in Lombardy and Veneto in the north and in Campania and Calabria in the south.

The centre-left is expected to hold on to Tuscany and Emilia-Romagna as well as three smaller regions thanks to rising voter confidence since the party elected a new leader, Pier Luigi Bersani, in October on pledges of internal reconciliation and dialogue with potential allies.

Four other regions that are currently in opposition hands could shift -- with more probability for Piedmont and Liguria in the north, less for Rome's Lazio region and southern Apulia, analysts say.

Two women are vying to become Lazio's next governor: former European commissioner Emma Bonino, a libertarian standing for the centre-left Democratic Party, and the PDL's Renata Polverini, head of the right-wing trade union UGL.

In Piedmont, Roberto Cota of the Northern League is running neck-and-neck with his left-wing rival Mercedes Bresso, according to recent polls.

Sunday's voting at some 50,000 polling stations opened at 8:00 am (0600 GMT) and was to continue until 10:00 pm, resuming Monday from 7:00 am to 3:00 pm.