The parties supporting Giorgia Meloni’s government such as the League, Forza Italia and her right-wing Brothers of Italy party, all backed the reform.
The main opposition groups, the centre-left Democratic Party (PD) and the 5-Star Movement (M5S), voted against.
The bill will now be examined by the floor of the Upper House.
Under the current system, parties engage in government-formation talks after a general election and then the coalition that forms a ruling majority in parliament agrees on a figure to propose to the head of State to become PM.
That figure is not necessarily one of the politicians given by the parties as their PM candidate during the election campaign.
Meloni says the Constitutional reform would ensure Italy is governed by leaders chosen by the people and would make administrations more stable.
She has said the centre-left opposition is against it because it will stop them getting to power via deals between parties.
The centre-left opposition PD has slammed the proposed reform as “dangerous”, saying that it “weakens parliament and the prerogatives of the President of the Republic”.
PD leader Elly Schlein described it as “a distortion of the Constitution and the parliamentary Republic”.
On Wednesday, M5S’s Alessandra Maiorino described the bill as “a TNT charge against our Constitutional architecture, without saying what the alternative to that architecture is, as it is only sketched”.
ANSA
