"They have emerged as the largest party. I want to congratulate the party," Pakistan Tehreek-e-Insaf vice-president Asad Umar told a Pakistani TV channel.
Trends from some 250 of 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 Tehreek-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 polls.