With less than 48 hours until polls open for Cambodia’s commune elections, Prime Minister Hun Sen this morning led a massive rally of Cambodian People’s Party supporters through Phnom Penh from the back of a flat bed truck.

With past commune elections a relatively low-key affair, and the premier having avoid the campaign trail for decades, his decision to head such a huge show of strength gave some indication of the importance of Sunday’s vote for the man who has led Cambodia for more than three decades.

The premier started the morning, fittingly enough, on Hun Sen Boulevard, south of the city, with an hour-long speech from a stage constructed on the roadside.

Taking to the lectern at just after 8am, the premier estimated the crowd numbered 200,000. While that figure couldn’t be verified, the assembled mass of motorbikes, tuk-tuks, trucks, cars and four-wheel drives stretched almost down the entirety of the nine-kilometre road, which became a sea of white CPP shirts and hats dotted by flags.

"Winning isn't just for the commune candidates, it is for the party and for the nation," the premier said after the national anthem finished.

"The rally today is to show support for those candidates.”

As the sun heated the tarmac and a drone buzzed overhead, the premier delivered a stump speech featuring familiar themes, reminding the crowd about his party’s role in toppling the Pol Pot regime and his “win-win” policy of attracting and absorbing ex-Khmer Rouge fighters into the government, and lauding the party’s track record of “development”.

“I would like to tell the nation that peace and development took place in this poor unfortunate country because of the CPP,” he said, later suggesting his leadership was fate.

“I did not expect I would have to solve all the problems of the old generation. Maybe god gave birth to me in order to solve all the problems that the older generation created.”

CPP supporters at this morning's rally led by Prime Minister Hun Sen, in Phnom Penh. Shaun Turton

It was a message that resonated with those in the crowd, which included many prominent Cambodian celebrities.

“They have brought development to the country from when the country was nothing,” said comedian Chuong Chy, also known as Koy, as the premier spoke.

Facing its toughest electoral challenge in decades, CPP has been accused of running a campaign of intimidation and threats against the opposition Cambodia National Rescue Party, with the premier and top military brass warning of “civil war” should the party lose power.

During his speech today, Hun Sen delivered a clear message to parts of the international community, which have been critical of his rule.

"Please foreigners, don't step into Khmer business,” he said.

He also pointed to recent changes to the Law on Political Parties, which vest authorities with the power to disband political parties, an amendment critics have said appears targeted at the opposition.

“Now, the law allows to dissolve any party if there is a proper complaint,” he said.

In warning parties against disputing the results, he also discussed allegations that the purportedly indelible ink used to mark voters was erasable with certain solvents.

“Winning over the CPP is not a child game,” he said.

“Please accept the result of the election; please don't say that the ink is erasable.”

Cambodians will on Sunday elect their representatives for the Kingdom’s more than 1,600 communes, in a vote that will give the first indication of where the electorate is leaning since the tight 2013 national election.

Standing in the crowd as the premier spoke, 28-year-old Chan Som Many said he believed the CPP was the practical choice.

“When the CPP says it is going to do something, it does something,” he said, accusing the opposition of “ripping off” the country.

Analysts have long questioned whether the prime minister would be willing give up power in the event of an opposition victory, an issue the premier touched upon in his speech.

“Some people said I should stop leading the country. Yes, I will do this, but so the people in the CPP can lead it,” he said.

Prime Minister Hun Sen gives an hour-long speech from a stage constructed on the roadside, on Hun Sen Boulevard, in Phnom Penh this morning. Shaun Turton

Sometimes cast as a populist, the premier took time to note the rise in the garment industry’s minimum wage to $153 a month, and noted his decision to scrap the requirement for driver’s licences.

“The opposition demanded that every one of them had to have driving licences. But CPP didn't agree,” he said.

Hun Sen did, however, appear at one point to acknowledge discontent with his three-decade rule, which has helped fuel the CNRP’s popularity under the banner of “change”.

“Please put your disappointment aside, and vote to make CPP win the election.”

After the speech, the premier boarded a flatbed truck, equipped with a podium, alongside senior CPP figures and tycoons, including former Foreign Minister Hor Namhong, the capital’s governor, Pa Socheatvong, and business tycoon Kith Meng.

In a well-organised procession, the truck moved slowly up Monivong Boulevard, followed by thousands of supporters, each in segments organised by district.

Taking to the microphone, he urged bystanders to give their support, addressing the many children lined up and down the road.

“Thank you, grandchildren. Only if you help vote for CCP will you have the ability to go to school without fear of being in danger of war," he said.

As the premier arrived at the Kuoch Canon Roundabout near the Japanese Friendship Bridge, he revealed to the crowd that the CPP had paid for several television stations to broadcast the rally live for “$300 per minute”.

After giving another speech from the back of the truck, the premier, flanked by bodyguards, made his way through a crowd of young CPP supporters and journalists.

His final words were a “blessing” to the party’s supporters, who will continue to campaign in their districts.

“It is time for me to finish. I have to say goodbye here. You have to continue the campaign in your district until the evening. We will meet each other again in the campaign for the parliamentary election in 2018,” he said.

Dressed in a blue CPP polo and resting on her motorbike, Nou Sophana said the party had her support.

“We have seen a lot of development such as skyscrapers and roads,” said Sophana, an accountant from Kandal province’s Takhmao town.

“Also he has made the international community know about Cambodia.”