“Last time, in 2008, I voted for the Pakistan People’s Party [PPP], but they have not even showed up to ask for our vote,” said Zulfikar, pouring his tea into a saucer and ducking his head to drink. “This time I will be voting for Nawaz Sharif because I think Nawaz Sharif is a great man.”

As Pakistan goes to the polls in an historic election, it is former Prime Minister Mr Sharif and his Pakistan Muslim League (PML-N) who are considered the front-runners.

Just six weeks ago they were the clear favourites. But even here, in his stronghold of Punjab, where his brother is the powerful provincial chief minister, it seems clear Mr Sharif will not have an entirely clear run at securing his third term leading the country; Imran Khan, the spirited, anti-incumbency candidate, is leading a ferocious late challenge.

The faces of Nawaz Sharif and his brother, Shahbaz, stare stridently from the countless thousands of PML-N flags and banners that fly across Lahore. (So, too, does the face of their mascot, a tiger, the real-life incarnation of which was this week reported to have become ill and died.)

And there is also a stridency about the insistence of their supporters that the Sharifs have delivered for the people. Development, jobs and infrastructure are cited as the brothers’ main achievements of recent years. A metro-bus system that helps transport 120,000 people every day costs just 20 rupees (13p) per trip.

“A journey that used to take more than two hours, now just takes 25 minutes,” said Asim Nazir, owner of a shop selling academic books in the city’s so-called Urdu Bazaar.

Another supporter drew a distinction between a clinic established by Imran Khan and the public hospitals that he had visited in the city. “I like Imran Khan, but a poor man cannot go to his hospital,” said Hamza Sharif, who works as a laundry man. “Nawaz Sharif has hospitals that are free.”

The Sharifs have also worked hard to appeal to younger voters, many of whom might be expected to support Imran Khan. A popular measure introduced over the past two years was the handing out of laptops to promising students – and solar panels for their homes to generate power during the country’s ubiquitous power cuts

The province of Punjab, which returns 148 members to the 272-strong national parliament, is the key to any national election in Pakistan. To return to office, Mr Sharif must bank on securing at least 100 seats and then look for coalition allies. The trouble for him is that Mr Khan, the former ?cricket star, is making a strong push.

“The reality is that the Muslim League is under pressure because of the inroads made by Imran Khan in Punjab, especially in those regions that were once strongholds,” said Rasul Bakhsh Rais, of Lahore’s University of Management Sciences.

He said some weeks ago, before a recent resurgence by Mr Khan, the calculation was the Sharifs might secure 130 seats. Now, he said, that figure might be 90-100, meaning they could not rule by themselves, and possibly making Mr Khan a kingmaker. A poll published by Pakistan’s Herald magazine, suggested Mr Khan and Mr Sharif may be neck and neck.

Observers say over the past five years, during the term of the PPP-led government headed by Asif Ali Zardari, Mr Sharif has played a strategic hand. While he withdrew his party from the PPP coalition within weeks of its being formed in 2008, following disagreement over restoration of judges, he declined opportunities to try to bring down the government. He realised the completion of a full term by a civilian government – any civilian government – would ultimately benefit him.

For many of the potential supporters Mr Sharif and Mr Khan are reaching out to, the most important issues are clear: ending the electricity and energy shortages that result in power cuts of 18 hours a day, nailing down inflation, and tackling corruption.