By Agustinus Beo Da Costa and Kanupriya Kapoor
GARUT, Indonesia (Reuters) - When Wawan Setiawan, a volunteer for Indonesian President Joko Widodo's re-election campaign, goes door-to-door in this conservative part of Java, his opening line is: "If you hear he is anti-Islam or a communist, remember, it's all lies."
The 41-year-old is one of thousands of volunteers - armed with T-shirts, stickers, pins, and other giveaways - seeking to bolster support for Widodo in the teeming villages of West Java, the most populous province and a key battleground in the April 17 vote in the world's largest Muslim-majority country.
Widodo's aides say such mobilising of grassroots support and canvassing of thousands of Islamic boarding schools in this and other conservative provinces is crucial to prevent a repeat of 2014, when a smear campaign accusing Widodo of being a bad Muslim beholden to Chinese interests nearly cost him the presidency, with the heaviest losses in West Java.
As in 2014, Widodo is running against retired general Prabowo Subianto, whose military background and strong ties with hardline Islamist groups make him a popular choice in West Java, with a voting population of 32.5 million, or about 17 percent of the electorate.
On a national level most opinion surveys give Widodo a double-digit lead, but he trails in West Java, which is known to be among the country's most conservative regions.
As conservative Islam gains greater traction in Indonesia, many politicians including Widodo have taken pains to appear "more Islamic" to appeal to Muslim voters. The worry for many investors is whether this appeal for conservative votes will translate into populist policy.
Around the hilly city of Garut, which favoured Prabowo in 2014, gigantic banners show the president dressed in a peci cap and sarong - traditional garb worn in Islamic boarding schools - saying, "let's pray".
To the disappointment of some of his more moderate and progressive supporters, Widodo also picked 76-year-old Islamic cleric Ma'ruf Amin as his running mate - part of a deliberate strategy to enhance his ticket's appeal among Muslims.
"The one thing that I really like about the Jokowi campaign is that they understand where they failed in 2014," said Achmad Sukarsono, a senior analyst at Control Risks in Singapore, using the president's nickname.
"They made a mathematical calculation that Jokowi lost in areas where the Muslim population was above 97 percent," he said.
Religious leaders say Widodo's most effective strategy has been forging closer ties with Islamic boarding schools - which hold huge cultural and social sway in many parts of Indonesia - and his decision to choose Amin as running mate, a respected Islamic scholar from the country's biggest moderate Muslim organisation, Nahdlatul Ulama.
"The key difference now is Jokowi has systematically shown his appreciation for pesantrens and santri," said a young cleric, Hilman Uman Basori, using the Indonesian words for Islamic boarding schools and their students.
Basori, who runs nine pesantrens in Garut, said Widodo has visited regularly, channelled funding, and introduced much-needed vocational training programs to complement religious education and allow graduates to find jobs.
"Picking Ma'ruf Amin as vice presidential nominee made the choice final for us...We have mobilised all the resources in our pesantrens to make sure they win," Basori added.
Aides say Widodo has also sought to appeal to more voters in opposition strongholds by making public appearances with his family and subtly drawing a contrast with his rival Prabowo, who is divorced.
But not everyone is convinced. West Java, which has a history of bloodshed between Muslims and leftists, remains a stronghold for conservative Islamists who harbour suspicions about Widodo, a moderate Muslim hailing from Central Java whose government has sought to crack down on some hardline groups.
"Jokowi has criminalised clerics and that has been very hurtful for the Muslim public," said cleric Cecep Abdul Halim.Authorities have launched investigations into prominent Muslim figures on charges of violating pornography laws or defamation. The government also banned the hardline Hizb-ut Tahrir Indonesia group, which advocates a caliphate to replace Indonesia's secular ideology.
Halim says he also suspects that Widodo, who is the first leader to come from outside Indonesia's military and political elite, may have links to communist groups - which are illegal in Indonesia - and is allowing "millions" of Chinese workers into the country.
The president has repeatedly denied such claims and urged voters not to be taken in by such falsehoods.
In late 2016, Widodo scrambled to distance himself from a one-time ally, the popular ethnic Chinese, Christian governor of Jakarta who was accused by hardline groups of insulting Islam. As hundreds of thousands of Muslims took to the streets to oust the governor, Basuki Tjahaja Purnama, Widodo sought to reassure Islamists and the broader public that his government was not anti-Islam.
Purnama eventually lost the next election for governorship, was jailed for blasphemy and released earlier this year.
Prabowo's provincial campaign team say voter dissatisfaction over these issues and Widodo's performance on the economy are swaying voters.
"We're not just optimistic, we are sure we will win," said Yusuf Supriadi, at a campaign post piled high with banners and t-shirts, as well as a poster of Prabowo calling to "Make Indonesia Great Again".
Surveys show that although Widodo trails in West Java, his focused campaign has narrowed a gap that in 2014 stood at 20 points. His support rose from 39 percent at the start of the campaign in September to 42 percent last month, while Prabowo's numbers have slipped from 50 to 47 percent.
"The hardest part has been changing public perception of Jokowi at the very grassroots level," said Yuda Puja Turnawan, a member of Widodo's party, the Indonesia Democratic Party of Struggle. "Our volunteers spend most of their time countering hoaxes."
According to his national campaign manager, Erick Thohir, the president's choice to reside in the presidential palace in the West Java city of Bogor, rather than in Jakarta, had also boosted his visibility in the region.
Since taking office, Widodo has also made efforts to bring religious parties into his coalition - something analysts say has provided more "tools in his arsenal to approach voters not reached in 2014".
Liberal supporters of Widodo have criticised him for pandering to conservatives, raising concerns over the erosion of Indonesia's reputation for religious tolerance and pluralism.
Analysts say Widodo's overtures to Islamic groups and voters point to a potential populist turn in policymaking if he wins a second term.
"There's a space opening for Islamic identity politics," political analyst Sukarsono said.
"What we will have is Jokowi having to accommodate the interests of the majority, the mainstream Muslim groups and the Islamic parties that backed him, in policymaking, so he is likely to become more populist."
(Additional reporting by Yerica Lai and Ed Davies; Editing by Raju Gopalakrishnan)