BEIRUT, Lebanon - Saad al-Hariri, the billionaire businessman and son of a slain former prime minister, is emerging as the favorite to lead Lebanon's government after his pro-Western coalition fended off a serious challenge from Iranian-backed Hezbollah in weekend elections.

Legislative allies said yesterday that Hariri, 39, the moderate leader of the largest parliamentary bloc in the winning coalition, is expected to replace his ally Fuad Saniora.

Hariri's alliance dealt a major setback to Hezbollah and its Syrian and Iranian backers in Sunday's vote, gaining 68 seats to the opposing group's 57. The three other seats in the parliament went to independents.

In a victory speech Monday, Hariri called on the Lebanese to close ranks.

"We must extend hands to each other, roll up sleeves, and work together for the benefit of Lebanon," he said.

His spokesman, Hani Hammoud, said yesterday that Hariri had repeatedly declared he would not shy away from the premiership but would consult with his allies first.

Hariri declined the position after the last elections in 2005, held just months after his father, Rafik al-Hariri, was assassinated in a car bombing in Beirut. His killing sparked huge street protests against Syria, which many including Saad Hariri blamed in the attack. Syria denied involvement.

The demonstrations, coupled with intense international pressure, forced Syria to pull its tens of thousands of troops out of Lebanon a few months later in what was a watershed moment in Lebanon's modern history. It ended nearly three decades of Syrian control of its smaller neighbor.

Over the last four years, Hariri faced death threats as he accused Syria of killing his father and others.

He was besieged in his Beirut residence for a few days when Hezbollah gunmen overran pro-government Sunni neighborhoods in street fighting in May 2008.

After the show of force, Hezbollah wrested an agreement that gave it veto power over government decisions. The deal virtually paralyzed the government over the last year but ensured relative calm.

Ahmed Fatfat, a member of Hariri's Future Movement, said he expected him to be nominated as prime minister during binding consultations between President Michel Suleiman with the new legislators after the parliament's term ends June 20.