Irrespective of the result, the Jakarta gubernatorial election on April 19 will leave a bitter aftertaste that could have consequences on the political landscape in the rest of Indonesia. The election is already billed as the ugliest, and most divisive and most polarising the country has ever seen.

Religion, and to a lesser extent, race, were issues that were widely exploited in the election. Rivals trying to unseat the hugely popular incumbent, Basuki Tjahaja Purnama, virtually forced Jakarta voters to decide whether a non-Muslim and an ethnic Chinese, hence a double-minority, could be allowed to govern the sprawling city of 10.5 million people.

Whether Basuki, or his challenger Islamic scholar Anies Baswedan, wins the run-off, the religious bigotry and racism that the election raised will likely linger on, or even spread further afterwards.

Pluralism, or the notion that this nation of 250 million people made up of diverse ethnic, racial, language and religious groups could live and coexist peacefully, looks like in serious jeopardy now, unless someone puts a stop to it. President Joko Widodo has stepped up to the plate, and he may have taken his cue from Indonesia's first president Sukarno by combining several ideologies into one. In his particular case, it is Islam and nationalism.

Indonesia, the country with the world's largest Muslim population, has defied the myth that democracy and Islam are incompatible by holding four peaceful democratic national elections since the downfall of strongman Suharto in 1998. Now President Widodo must show that Islam and nationalism are also not only compatible, but that the two can work together to preserve national unity.

Jakarta is considered a political trendsetter and the whole nation is watching the election to get a sense of how deep religion now plays in national politics. Not that Indonesia needs more of it. Religious intolerance is already on the rise in recent years with many minorities becoming the target of attacks. The ugly election campaign in Jakarta is bound to put more pressure on the religious minorities and more strains on overall interfaith relations.

Two big demonstrations in Jakarta, in November and December, that were ostensibly aimed at stopping the re-election of Governor Basuki were part of a persistent campaign to push Islam into the centre of the political stage and then drum up support for whatever agenda their sponsors have, including the sharia to replace the law of the land, and an Islamic state down the road.

This is making not only the religious minority groups restless, but also many Muslims who don't necessarily agree with the Islamist agenda.

Although nearly 90 percent of Indonesia's population are Muslims, Indonesia is not an Islamic state, a decision its founding fathers consciously made upon independence in 1945 to placate religious minorities like Christians and Hindus, particularly from eastern Indonesia. These eastern provinces would have happily opted out of the new republic and formed their own independent states if the former Dutch colony had gone Islamic.

Indonesia's secular status has since survived many tests, including a series of armed rebellions and terrorist attacks in the name of Islam. But now the battle by the Islamist proponents is primarily being waged in the public space. With the help of the Internet, which has created an open market place for ideologies, this fight has become about winning the hearts, minds and soul of the people.

President Widodo is leading the campaign to stop or reverse the rise of Islamism. He does so by raising the spectre, rightly or wrongly, that the nation's unity is at stake because its key underpinning, pluralism, is being attacked by those who want to turn Indonesia into a theocratic state. And he does so not by tackling Islam head on, but rather by embracing the religion without losing sight of the bigger interests of preserving the unity of this very diverse nation.

He is combining Islam and nationalism into a single powerful force for national unity, development and prosperity.

This is reminiscent of the founding father Sukarno, who, as a young 26-year-old revolutionary thinker, penned an article in 1926 about synthesising Islam, nationalism and Marxism, which he saw as the main political pillars for the independence struggle. These three are competing ideologies, Sukarno wrote, but their combination would portend for a force that the Dutch colonial rulers could not stop.

After independence in 1945, president Sukarno tried to rally the three pillars together again, this time with disastrous and fatal effects. The communist party was crushed for good and Sukarno lost power in 1966.

Widodo is not as academically inclined, but he can be as astute a politician as Sukarno was.

His campaign in recent months has taken him to meet with top leaders of the military, the main force to preserve national unity, to secure their support and loyalty, telling them that he is fighting against the forces that are undermining the Unitary State of the Republic of Indonesia (NKRI).

He called a press conference during his visit to the headquarters of the Special Forces saying that in his capacity as Indonesia's commander-in-chief, he could deploy the country's most fearsome and revered military division anywhere in the country to quell any threat to the state's pluralistic status.

He has met with leaders of the Muhammadiyah and Nahdlatul Ulama, the country's two largest Islamic social organisations, to get them on board of his NKRI campaign, and to make their leaders publicly denounce the forces that threaten national unity and get them to say that all Muslim citizens have the obligation to support the state and its policies.

These two organisations, with their massive influence among Muslims in Indonesia, have been responsible in developing the more tolerant and moderate version of Islam in the country, and in the past have been counted on to fight against the rise of radical Islam. And now Widodo is turning to them once again.

Has the President done enough to stop the creeping Islamism in Indonesia? Time will tell. And somehow, the Jakarta election, whichever way it goes, would also be a telling factor about which direction Indonesia is heading.

The writer is Editor-in-Chief, The Jakarta Post, Indonesia.

This is a series of columns on global affairs written by top editors and columnists from members of the Asia News Network and published in newspapers and websites across the region.