Also, Ikramullah Gandapur, a candidate from Mr. Khan's Pakistan Tehreek-e-Insaf party, and his driver, were killed by a suicide bomber in northwest Pakistan on Sunday.
It also postponed the balloting for the National Assembly seat from the garrison city of Rawalpindi, where a candidate from former prime minister Nawaz Sharif's party was disqualified after being convicted of substance abuse.
Many experts contend that it will be business as usual whoever wins the election, with the military - which has ruled the country directly or indirectly for much of its 71-year history - remaining Pakistan's de facto ruler.
There is public holiday on Wednesday so that the people could exercise their right to vote without any hindrance.
Voting for those two seats would take place at a later date.
Amazon Prime Day seen setting new sales record for e-commerce giant
Earlier this year, the company said it surpassed 100 million Prime members , but Amazon hasn't disclosed official numbers since. Amazon is hoping its deals, available only to Prime members, are a hit with customers as it's raising the price of the program.
Another 70, reserved for women and minorities, are distributed between parties that win at least 5% of the vote.
After his younger brother's death, Gandapur was elected as a member of the assembly of Khyber Pakhtunkhwa province and appointed provincial minister for agriculture.
Critics have long accused Pakistan's powerful military, including its Inter Services Intelligence (ISI) agency, of meddling in politics and judicial affairs, a charge it denies.
Addressing a rally in Sargodha late on Saturday, the PML-N chief said: "If I do not end [the] load shedding crisis in six months, you can change my name", adding "they (Indians) will come to Wahga Border and call Pakistani's their master".
As the early voters queue up outside polling stations, the question on everyone's mind will be whether Mr Khan will be the next prime minister.
Walmart is considering its own cheap, ad-free video streaming service
A host of new shows and movies are coming to Amazon Prime Video including oldies, newbies, and originals. For the first time iD mobile is included in the data as it now has a stable 1.5 per cent market share.
Former Pakistani cricket stars have come out in support of the cricketer-turned-politician as the country prepares to go to the polls.
However, the PML-N could reap a sympathy vote after Nawaz Sharif returned to be arrested on July 13 along with his daughter Maryam, leaving his cancer-stricken wife in a London hospital.
During Pakistan Election 2018, 53,000 local, national, and worldwide media observers will monitor the polls.
But Imran Khan and his PTI have been rising in the polls.
Now fronted by Ms Bhutto's son, Bilawal Bhutto Zardari, a 29-year-old Oxford University graduate, the party is promising to create a "peaceful, progressive, prosperous, democratic Pakistan".
'Better Than Super': Russia Reacts To Trump-Putin Summit In Helsinki
I think it's rare, though, for someone to say "would be" when he means "wouldn't be". Coats, 75, is not known as being flippant. I will tell you though, it better not be.
The prime minister-designate of Pakistan's Muslim League party pledges to emulate Mahathir in developing Pakistan.