Joko Widodo, Indonesia's president, left, speaks while Ma'ruf Amin, vice presidential candidate, listens, during a first presidential debate in Jakarta, Indonesia, on Thursday, Jan. 17, 2019. Dimas Ardian | Bloomberg | Getty Images

As Indonesians head to the polls in April, religion and the economy will likely take center stage as President Joko Widodo seeks re-election, experts told CNBC. Commonly known by his nickname "Jokowi," the incumbent president is up against former Lieutenant General Prabowo Subianto in the upcoming elections — a replay of the 2014 elections. Both candidates had previously faced off in the 2014 polls which saw Widodo narrowly defeat Prabowo after garnering 53 percent of the votes. While Widodo is currently leading in opinion polls, his chances of re-election are contingent on his religious credentials and ability to push Indonesia's economy forward. Like the previous election, it is difficult to determine the winner beforehand because the "support for candidates are so close," Alexander Raymond Arifianto, a research fellow at the S. Rajaratnam School of International Studies in Singapore, said during an interview with CNBC's Capital Connection on Friday.

Religion a 'salient issue'

However, religion and identity politics are a "far more salient issue" in this year's elections, Arifianto said. He explained that identity politics — which he defined as the usage of religious and/or ethnic symbols by certain groups of people for their own political ends — could be one of the key deciding factors of Widodo's election success. Religion is playing an increasingly important political role in Indonesia, which has the largest Muslim population in the world. Widodo's selection of the highly influential Muslim cleric Ma'ruf Amin as his running mate has been seen by many as a move to enhance support from conservative religious groups. Rallies against Jakarta's governor in 2016 had cast serious doubt on Widodo's religious credentials after his ally, Basuki "Ahok" Tjahaja Purnama, was imprisoned on charges of blasphemy. "Ahok" — the capital's first Chinese Christian governor — was found guilty of insulting the Quran after making references to the religious text in his rally speech. Those protests quickly spread, with opposition supporters using it as a platform to criticize Widodo's government. Some of those Islamic protesters are now backing Prabowo, according to Arifianto. Although Widodo is leading in double digits in the opinion polls and has far more financial support than Prabowo, the former lieutenant general has far more "hardcore, die-hard supporters — mainly from this Islamist camp," Arifianto noted. "They are going to back (Prabowo) no matter what, and they are going to support him in a lot of provinces, like West Java and Banten, that have strong Islamic undertones in their population," he said, adding that those supporters might be able to turn the tables around.

Economic promises