Italy's election appears to leave a hung parliament in which no single party or coalition commands an overall majority according to projections based on preliminary results, leaving few options for any new government.
The prospect of a grand coalition between Silvio Berlusconi's Forza Italia (Go Italy) party and the ruling centre-left Democratic Party against the surging populists and far-right appears no longer feasible.
Here are three main possible scenarios:
Populist, far-right alliance
Both the anti-establishment Five Star Movement and the far-right League party have ruled out the possibility of a post-election pact but this is currently the only option that looks like it would command a majority.
According to the latest projections, the two parties together would hold 355 seats in the 630-seat lower house of parliament and 168 seats in the 315-seat upper house.
Both parties are heavily eurosceptic and League leader Matteo Salvini has been accused of stirring up racial tensions. A tie-up could cause shockwaves around Europe.
Preliminary results make this remote as the coalition is predicted to win only 37 percent of the vote, including 18 percent for the League and 14 percent for Silvio Berlusconi's Forza Italia (Go Italy) party.
The final result of the vote in terms of seats is hard to predict, however, as Italy is using a new electoral law for the first time that combines proportional representation with a first-past-the post system.
If the coalition does win a majority and the League comes in ahead of Forza Italia, this would open the prospect of far-right Salvini being nominated as Italy's next prime minister.
If there is no clear majority, President Sergio Mattarella could choose to leave in place the current centre-left government of Prime Minister Paolo Gentiloni.
This would allow time to set up a temporary government to reform the electoral law and organise new elections.
But the process would take time as consultations could only start after parliament's newly-elected lawmakers meet for the first time on March 23 to elect speakers.
After a stalemate following Italy's last election in 2013, it took more than two months to form a government.