Java was a crucial region in winning the 2019 presidential election. The number of votes from six provinces on Java Island in the 2014 presidential election contributed 58.6% of the total 133.57 million valid votes. Prabowo Subianto's vote count in Java contributed 60% of his total national vote, while Joko Widodo's contributed 57.26% of his total vote in the 2014 presidential election.
In the 2014 presidential election, Jokowi, paired with Jusuf Kalla (JK), won in four provinces: Central Java, East Java, DKI Jakarta, and Yogyakarta, obtaining 40.65 million votes. Meanwhile, Prabowo Subianto, paired with Hatta Rajasa, only won in two provinces: West Java and Banten, with 37.63 million votes. In total, Jokowi won by more than three million votes in Java.
Jokowi's largest vote contributions came from Central Java and East Java. Central Java is Jokowi's hometown. East Java is a stronghold of the Indonesian Democratic Party of Struggle (PDI-P), the party that nominated Joko Widodo. To win the 2019 presidential election, both Jokowi-Ma'ruf Amin and Prabowo-Sandiaga Uno needed to win the vote in Java. That was the key.
(Read Databoks: LSI Survey: PDI-P has a chance to win the 2019 Legislative Election again)