Hundreds of thousands of Indonesians in the city of Makassar headed to local election polls to cast a blank vote rather than elect the only pair of candidates from the same coalition, according to quick count surveys.

Key points: Votes swung strongly towards Mr Jokowi in West Java

Votes swung strongly towards Mr Jokowi in West Java More than half of Indonesian voters take into account the candidate's religious background

More than half of Indonesian voters take into account the candidate's religious background Jokowi's political opponents had leveraged the feeling of isolation among conservative Muslim voters

And it's not the only city where this has happened — voters in 13 other regions also voluntarily gave up their time to cast a blank vote to protest against the political and economic elites who nominate the candidates.

"It was quite a slap in the face to the establishment … people are very much more focused on the candidate rather than the party," said Tim Evans from governance organisation Kemitraan, an expert on Asian elections.

"[Voters' loyalty] to parties is quite rare here, people can switch parties quite easily — often what we see are people looking at performers."

It's good news for a populist style President like Joko "Jokowi" Widodo who is seen as an outsider to the establishment.

However, he faces a serious challenge as he attempts to deal with policies that could give conservative Muslims reason to turn against him.

This was demonstrated by his reluctance to apply a proposed presidential decree, known as "Perppu", to ban child marriages, and in his anti-leftist rhetoric when he denounced the PKI (Communist Party of Indonesia).

The issue blew up earlier this year after the marriage of a 14-year-old girl and 15-year-old boy in Sulawesi went viral after high profile attempts to stop the union failed.

The regional elections in Indonesia's 171 voting areas has been widely seen as a precursor to the upcoming 2019 presidential race where Mr Jokowi faces a difficult task balancing the demands of Islamic conservatives, more progressive voters in major cities like Jakarta, and those in the regions who are dissatisfied with the governing elite.

Election exposes religious divide

Muslim protesters march during a protest against Jakarta's Christian Governor Basuki "Ahok". ( AP: Achmad Ibrahim )

Poltracking Indonesia which monitors voter sentiment found 58.5 per cent of Indonesian voters take into account the religious background of the presidential and vice presidential candidates.

This could be an issue for President Jokowi, who historically hasn't been popular with conservative Muslim constituencies, said Vedi Hadiz, Deputy Director of Asian Studies at the University of Melbourne.

"[Jokowi's] social background does not suggest strong Islamic credentials and that could work against him," he said.

Indonesian President Jokowi wants to avoid controversy. ( Reuters: Beawiharta )

Australia National University PhD candidate Thomas Power said President Jokowi's political opponents have jumped behind the movement which saw the removal of the Christian-Chinese governor Basuki Tjahaja Purnama, also known as Ahok.

"The primary narrative of Jokowi's Islamist opposition emphasises the perceived lack of representation of conservative Muslims in Jokowi's Government, as compared to the Yudhoyono era," he said.

Mr Hadiz said politicians have played up the religious morality card to deflect criticism, but also to "encroach upon the constituency of parties that are more Islamic".

He added that Ahok's alleged blasphemous comments "provided ammunition for a movement to develop, which resulted in [his imprisonment]".

"This is exactly what Jokowi would want to avoid — he'd want to avoid controversy.

The ferry explosion occured on route from the island of Bali to the Gili Islands ( ABC/Roxanne Taylor )

"Since the anti-Ahok demonstrations, Jokowi has become extremely aware of the need to supply patronage to mainstream Islamic organisations," Mr Power said.

"He wants to limit the effectiveness of campaigns by more staunchly Islamist groups that portray Jokowi's Government as anti-Islamic."

Jokowi should head 'much more relaxed' into election

Prabowo Subianto with Indonesia's President-elect Joko Widodo. ( Reuters )

Despite the difficulties Mr Jokowi faces in appealing to religious conservatives, a survey by Indonesian think tank Saiful Mujani Research Centre found that candidates backed by Mr Jokowi, or parties in his coalition, have done well in early polls in the key areas of West, Central and East Java so far in the regional elections.

The results bode well for another term for Mr Jokowi, who Mr Evans said should go in "much more relaxed" than in previous presidential elections.

"West Java, for example, which was a very good province for his opponent General Prabowo in the last elections, [had] about a 60 per cent-40 per cent division in his favour," he said.

"This time [it] appears to be swinging quite strongly towards Jokowi — and that's the largest province in the country."

However, Mr Hadiz warned Mr Jokowi shouldn't be complacent, as the momentum could still change.

Surveys conducted by Indonesian political research organisation Poltracking found 53 per cent of the public may change their mind in the lead up to the 2019 presidential election.

In the regional elections, political oppositions performed better than expected.

"Even in places where they lost, they did far better than some of the opinion polls had suggested about a month or so ago … I think it would hearten them in the upcoming 2019 legislative and presidential election," Mr Hadiz said.

For example, in Central Java, the more conservative Prabowo Subianto backed duo, Sudirman Said and Ida Fauziyah, received 40 per cent of votes in early polls, higher than the predicted 20 per cent.

"What this shows is that they are able to harness some of the sentiments [of] religious conservatives within the broader electorate, and they will be able to do this at a level which is much greater next year so they can launch a more formidable challenge on Jokowi," Mr Hadiz said.

Polling materials in Central Java ahead of Indonesia's local elections. ( ABC: David Lipson )



