The Italian presidency is up for grabs on Monday when lawmakers elect the successor of incumbent President Sergio Mattarella.

More than 1,000 members of the two chambers of parliament – the Chamber of Deputies and the Senate – as well as representatives of the regions and autonomous provinces, will cast their votes from 3 p.m. (2 p.m. GMT).

There are traditionally no official candidates in the race, but current Prime Minister Mario Draghi has long been considered the favorite for the highest office in the state. Because he cannot hold both positions, negotiations have been ongoing for weeks in Rome about how to proceed with his government, in which almost all the major parties in parliament are represented.

Former Prime Minister Silvio Berlusconi announced he was withdrawing from the race on Saturday. Neither right-wing parties nor the leftist spectrum had agreed on a joint candidate by Sunday.

That makes a decision unlikely on the first day of voting, as a two-thirds majority is needed for victory in the first three counts. After that, absolute majorities suffice. With only one ballot scheduled per day, a winner is not expected before Thursday.

The president is elected for a seven-year term by an electoral college comprising 1,009 people. It is made up of members of the two chambers of parliament – 630 deputies and 321 senators – plus 58 delegates of Italy's regions.

In the first three rounds of voting, the winner must secure at least a two-thirds majority. From the fourth round, an absolute majority is enough. Ballots are cast in secret and in-person in the debating hall of the lower Chamber of Deputies, with only one round a day planned due to COVID-19 rules.

With the coronavirus currently widespread in Italy, a drive-thru voting station has been set up in the car park to allow those infected to cast their ballots from their vehicles.

The president is head of state and upholds the Constitution of Italy, which became a republic following a referendum after World War II. Key roles include naming the prime minister and, on the latter's advice, government ministers. The president has the power to dissolve parliament, in consultation with the speakers, and ask it to reconsider legislation.

Arbitrating in this way becomes crucial in times of political crisis – it was Mattarella who brought in Draghi as prime minister in February 2021. The president also appoints one-third of members of the constitutional court and has the right to pardon.

Draghi – a career economist with no political affiliation – appeared to hint at his availability in December, calling himself a "grandfather at the service of the institutions."

He is facing opposition from Berlusconi's Forza Italia party and also Matteo Salvini of the anti-immigration League party, who says he should stay where he is.

"It would be dangerous for Italy in a difficult economic time ... to reinvent a new government from scratch. It would stop the country for days and days," Salvini told reporters on Sunday.

But Enrico Letta, leader of the center-left Democratic Party, said Draghi had been an "extraordinary resource" for Italy and insisted talks would continue, telling Rai television, "Draghi is one of the hypotheses on the table."

Draghi, a former European Central Bank (ECB) chief brought in to lead a national unity government one year ago, is widely considered the most eligible candidate. But many fear his departure as premier could trigger chaos as Italy recovers from the devastation of the coronavirus pandemic.

With the disparate parties in Draghi's coalition already in battle mode ahead of next year's general elections, further instability could put European recovery funds at risk.

"This is a key and very complicated election, because the political parties are weak, they are in an utterly fragmented state," Giovanni Orsina, head of the Luiss School of Government in Rome, told Agence France-Presse (AFP).

Italy has a notoriously unstable electoral system and has seen dozens of governments come and go since World War II – with outgoing president Sergio Mattarella himself seeing five during his seven-year term.

But Draghi, brought in by Mattarella in February 2021, has led a remarkably united government comprising almost all of Italy's political parties.

Italy, the eurozone's third largest economy, has returned to growth following a punishing recession in 2020 sparked by the pandemic.

And Draghi has initiated key reforms demanded in exchange for funds from the European Union's post-pandemic recovery scheme, of which Rome is the main beneficiary, to the tune of almost 200 billion euros ($225 billion).

Many international investors are concerned that debt-laden Italy would slip behind on the tight reform schedule should Draghi step down as prime minister.

Others say Draghi would be better placed as president to ensure political stability and good relations with Brussels – particularly should the far-right win the next election.

The 74-year-old himself, credited with saving the euro from a debt crisis while ECB chief, hinted last month he is interested in moving to Rome's Quirinale presidential palace but has since kept his silence.

The secret nature of the ballot has thrown up some surprises in the election of 12 presidents since 1948 – only one of whom, Giorgio Napolitano (2006-2015), was elected for a second term. The role does not traditionally go to a party leader, but someone viewed as above the political fray. However, the favorite going into the race often comes away empty-handed.

In 2013, former Prime Minister Romano Prodi was nominated by the center-left Democratic Party but was betrayed by some of his supporters and Napolitano won.

The president's formal residence is the Quirinale palace, once home to the popes and kings of Italy. Perched on the hill of the same name, the sprawling 110,500-square-meter building is one of the largest presidential palaces, surpassed only by Turkey's.

Construction began in 1573 for the summer residence of the popes. It became their base as secular rulers, with the Vatican retaining their seat of spiritual power. Around 30 popes resided there, from Gregory XIII to Pius IX.

Under French rule, Napoleon ordered renovations to make it his Roman residence, but never set foot there. The Italian royals lived there from 1870 until the declaration of the republic in 1946 when it became the residence of the head of state.