"They have emerged as the largest party. I want to congratulate the party," Pakistan Tehrik-i-Insaf Vice President Asad Umar told a Pakistani TV channel.
Results and trends from the 272 parliamentary seats that went to the polls showed that the PML-N was set to bag in excess of 110 seats, while the Pakistan People's Party and Imran Khan's Pakistan Tehrik-e-Insaf were lagging far behind with about 35 seats each.
To win a simple majority, a party or coalition would have to bag 137 of the 272 National Assembly seats for which polls were held.
Another 70 seats, reserved for women and non-Muslims, will be allocated to parties according to their performance in the polls.
With this, Nawaz Sharif was set for a third term as Pakistan's prime minister
Of the results known so far, his PML-N has won 39 seats while the PTI has won 16 and the ruling Pakistan People’s Party has bagged just 11 seats.
Addressing a group of jubilant supporters at his home in Lahore, Sharif proclaimed victory for the PML-N and asked people to pray that the final results, expected to be announced on Sunday, would show an "absolute majority" for his party so that he would not have to lead a weak coalition.
"The results are still coming in but we almost have confirmation about one thing -- that the PML-N has emerged the largest party in this election.
"I ask you to pray that the results that come in the morning will show that the PML-N can form the government without outside support, so that the PML-N doesn't have to seek support from anyone," he said.
Sharif vowed to deliver on all the promises he had made during the campaign, including pledges to end crippling power cuts, set right the economy and to counter corruption.
"Our agenda and programme is to change the condition of the people. We should decide to change our condition because God only helps those who decide to help themselves," he said.
The two-time former premier also struck a conciliatory note, appealing to all parties to sit together with the PML-N to find ways to tackle Pakistan's pressing problems.
The PML-N's strong performance will make it possible for Sharif to form the government at the centre with the backing of independent candidates and smaller right wing parties like the Jamiat Ulema-e-Islam, analysts said.
Sources told PTI that the PML-N would also not be averse to working with the PPP after forming government as the party's leaders were not keen on an alliance with Imran Khan's Pakistan Tehrik-e-Insaf.
To win a simple majority, a party or coalition would have to bag 137 of the 272 National Assembly seats for which polls were held.
Another 70 seats, reserved for women and non-Muslims, will be allocated to parties according to their performance in polls.
To have a majority 342-member National Assembly, a party or coalition would need 172 seats.
Sharif, 63, served as premier during 1990-1993 and 1997-1999 but was ousted from office before he could complete his term – once on corruption charges and later because of a military coup led by Pervez Musharraf.
After being deposed in 1999, he was jailed and sent into exile to Saudi Arabia.
He returned to Pakistan shortly before the 2008 polls and rebuilt his party, which has also returned to power in Punjab, the country's most populous and politically crucial province as it has more than half of the seats in the lower house of parliament.
Pakistan poll promises: Peace, not posturing with India
Pakistan Polls: The men who MATTER
Imran Khan concedes defeat, Sharif set to return as PM
Pak polls: Nawaz, Imran win seats; PML-N leads
Don't have too many expectations from new Pak govt