In early December Ahmad Zakarsih, a 34-year-old school administrator and Bekasi resident, left his house at 6am for the 28km journey to the capital.

The proud owner of a Jakarta identity card that gives him the right to vote in the city’s upcoming gubernatorial election, he went there to protest against Jakarta’s governor, Basuki Tjahaja Purnama, widely known as “Ahok”, who is on the ballot this week.

Purnama stands accused of insulting the Koran during a campaign stop in Jakarta’s Thousand Islands constituency last October. With the vote just days away, he remains on trial for blasphemy.

Zakarsih had a simple reason for joining the more than 200,000 protestors – one of Indonesia’s largest demonstrations: “I felt I was answering a call of nature. To my mind, Purnama had shown disrespect to Islam.”

That’s not to say that he’s always been anti-Purnama: “I could well have voted for Ahok if he hadn’t been involved in the case. In fact, I have no problem if Ahok isn’t imprisoned because if he truly is guilty, then Allah will punish him anyway.”

As an alumnus of the Pesantren Tebuireng, one of Indonesia’s most celebrated residential religious schools, and thoroughly versed in Islamic theology and philosophy, Zakarsih has the confidence of a man with an elite education, however modest his means.

Zakarsih is Betawi, one of the original peoples of the Jakarta region. The community’s most famous scions include the dangdut (Indonesian folk music) icon Roma Iroma, who sported a kitschy, Elvis-like look combined with staunchly conservative views.

However, over the decades, the Betawi have steadily left the centre of the vast 28-million-strong conurbation, selling their strategically located homes and rice fields to throngs of new arrivals – Javanese, Chinese and Arab Indonesians.

Most of the Betawi were supporters of Fauzi Bowo, the governor of Jakarta whom Joko Widodo defeated in 2012 on his way to winning the Indonesian presidency in 2014. Purnama was Widodo’s running mate and hence, in some minds, “inherited” the governorship. Hardliners in the Betawi community have arguably never been reconciled to these newcomers.

Zakarsih’s home in a corner of the now-booming, 2.6 million-strong Bekasi – Indonesia’s fourth largest city – is all that’s left of a small family farm replete with orchards and sawah (rice paddies). “There were 11 of us and my parents had to sell land to educate us all. Back in 1998 when I went to Tebuireng, my boarding and tuition fees were 60,000 rupiah [HK$35] per month,” he said.

After completing his degree, Zakarsih worked for four years in Siak on the island of Sumatra as a religious teacher, marrying in his last year. It was an arranged match. Then he returned to Bekasi.

Both he and his wife work. They have a one-year-old boy and are planning more children.

Every evening, he gives free Koran classes to local children, which he enjoys immensely. The children call him Pak Ustad (Mr Religious Teacher).

They also play devotional music with drums and stringed instruments.

Despite the vast amounts of money being poured into Bekasi’s infrastructure – from toll roads to light rail systems – Zakarsih is an unflinching critic of the current administration.

“Things are much tougher now than ever before. There’s more ‘outsourcing’ and all these government cards for health and education are very difficult to apply for. Islam has also fallen badly behind.”

Much has been said about what motivates those who oppose Purnama. Politics, and the gubernatorial election in particular, has often been portrayed as a straightforward contest between fundamentalism and secularism, prejudice and pluralism – “black and white” or “good versus evil”.

Talking to Zakarsih however, with his cryptic language studded with religious phrases, one gets a sense that there is more than meets the eye.

For a start, many of the more conservative Muslim groups who enjoyed privileged access and influence during the years when Susilo Bambang Yudhoyono was president feel excluded by the current centrist ethos.

Zakarsih was cryptic when asked how he would vote, offering a half-smile and explaining that he would be conducting a special prayer to seek guidance – the sholat istikhara h.

“Who knows,” he added, “maybe I’ll be moved to vote for Ahok?”