Polls have opened in Singapore for an election that is widely expected to see the ruling People’s Action Party (PAP) stay in power.

However, for the first time ever, opposition candidates are running in all constituencies, and could gain seats.

It is also the first election since the death of long-term leader Lee Kuan Yew, founder of the ruling PAP and the prime minister’s father.

The PAP has won every election since Singapore’s independence in 1965.

The PAP’s success has been attributed to its widespread popularity among Singaporeans – who have seen their country rapidly evolve into a first-world economy – as well as its tight political control.

Government stumbles in managing immigration and infrastructure, coupled with a greater desire by younger Singaporeans for political plurality, has led to increasing gains by opposition parties over the years.

The PAP’s biggest competition is the Workers Party, which in the last parliament had seven members of parliament out of 87 seats, but a number of smaller parties are also running. The next parliament will have 89 seats.

In previous elections, the PAP has retained some of its seats without a vote – known as a walkover – as no opposition candidate ran against them. But this year every seat is being contested.

The voting comes at the end of a colorful but brief nine-day election campaign period.

At least two million Singaporeans are expected to cast their vote at polling stations which will close at 20:00 local time on September 11.

The elections department, for the first time, will be announcing sample counts soon after voting closes. Opinion and exit polls are not allowed in Singapore’s elections.