ITALY'S Romano Prodi is scrambling for support ahead of a vote of confidence this week, which he must win to stay on as prime minister.

Prodi resigned last week after suffering an embarrassing defeat over foreign policy in the upper house. Italy's president gave him a second chance Saturday by asking Prodi to remain as premier and put his majority to the test in parliament.

Prodi needs to prove he has enough support in both chambers of parliament to keep his government afloat.

While his fractious Catholics-to-communists coalition has a comfortable majority in the lower house, in the 315-seat Senate his bloc is effectively level with the opposition, forcing him to court outside senators for support.

Prodi appears to have won the backing of one extra senator, a Christian Democrat who served in Silvio Berlusconi's previous center-right government as deputy prime minister.

Barring defections, that would raise Prodi's support to 157 elected senators, against 156 for the opposition, with one independent still up for grabs. The Senate speaker, who hails from the center left, traditionally does not take part in votes.

Prodi is also relying on the votes of four out of seven senators-for-life, un-elected elderly statesmen and prominent figures on whom he has depended heavily since taking office in May after the closest election in Italy's post-war history.

Their support failed to offset a revolt by his leftist allies in Wednesday's Senate vote.

So tight are the mathematics that the confidence vote in the upper house is not expected before Thursday to allow one of the Prodi-friendly life senators -- 97-year old Nobel medicine laureate Rita Levi-Montalcini -- to return from a trip to Dubai.

Commentators said Prodi is likely to pass the tests, largely thanks to the center left's fears that a defeat would clear the way for Berlusconi -- who is calling for an early election -- to return to power.

But they say splits within his coalition, over anything from Italy's military presence in. Afghanistan to pensions reform and rights for gay couples, are bound to resurface soon.

(SD-Agencies)