MEDAN, Indonesia - Five years ago, cobbler Feizal Lutfi voted for Golkar, but now he says he is switching to its longtime rival, Indonesian Democratic Party - Struggle (PDI-P).
The reason: PDI-P's presidential candidate Joko Widodo, better known as Jokowi.
"He cares about the common man's struggle. Unlike previous leaders, he works hard and hits the ground tirelessly," said the 53-year-old resident of Medan, Sumatra, known for its many loyal Golkar voters.
Mr Feizal's switch of political allegiance is being played out on a wider canvas. Sumatra, with 40 million voters, accounts for 120 of the 560 seats in the national parliament and is the biggest vote bank outside the Java heartland.
President Susilo Bambang Yudhoyono's Democratic Party won 36 of the seats in 2009, but is struggling in this election. Observers tip the spoils this time will be fought between Golkar, now with 25 seats, and PDI-P, with just 13.
While the so-called "Jokowi effect" is also stirring up things in provinces in Sulawesi and Java, its inroads into Sumatra are especially significant because it sets up a battle between two long-time rivals.
PDI-P traces its origins to the Indonesian National Party of founding president Sukarno, while Golkar is the party of his successor, former president Suharto.
Golkar chairman and aspiring president Aburizal Bakrie brushes off talk of serious inroads being made by PDI-P, led by Sukarno's daughter Megawati Sukarnoputri.
"What's there to be worried about? We are strong here," he told The Straits Times before stepping onto the stage at Thursday's rally in Medan city's iconic Lapangan Merdeka, or Freedom Square.
"Choose a party with a proven track record... elect a leader with experience" was the former coordinating welfare minister's message to some 3,000 supporters, one that emphasises Golkar's establishment credentials against Mr Joko's relative inexperience.
Golkar has now mobilised 50,000 campaign chiefs across the country to reach out to voters. Madam Yunie Tababan, 63, who was transported to the rally from the city outskirts, said she was grateful to Golkar for its help when her husband died recently.
"A Golkar social worker provided me with free ambulance service and some allowance to help me cope with my husband's death as he was the breadwinner," she said. The chief of the North Sumatra Golkar branch, Mr Ajib Shah, said it is outreach work such as this that ensures Golkar's success at election time.
"We have experienced grassroots people with good networks who know their constituents well," he said.