"Political contest for the legislative as well as the presidential candidates was still relatively tight because about half of the respondents stated their decision may change," CSIS researcher Philips Jusario Vermonte said at a press conference here on Monday.
One of the factors that may change their decision was news about political parties involvement in corruption cases, which may emerge before the elections, he said.
Based on the results of face-to-face interviews with 1,200 respondents, CSIS had found that 45.8 percent of the voters were not certain about their choices and may change their decision.
A total of 42.4 percent voters were certain with their choices and 11.8 percent had refused to give an answer.
With regard to the 12 national political parties that will contest in the elections, Hanura was ranked first in terms of its voters certainty of their choice.
"Based on the results of our research, most of Hanuras voters were certain of their choice. A total of 62.5 percent of Hanuras voters said they were certain of their choice," Philips added.
PKS voters followed in the second place, with 58.5 percent of them saying that their choice is already fixed.
Golkar was ranked third with 57.9 percent of its voters already decided, followed by Gerindra with 52.9 percent, PPP with 52.4 percent, PDIP with 48.1 percent, Nasdem with 44.7 percent, the Democrat Party with 43.5 percent, PAN with 38.6 percent, PKB with 36.3 percent and the rest or 3.2 percent still undecided.
The survey was conducted from March 7 to 17, involving 1,200 respondents interviewed at random neighborhoods, including heads of families and respondents.
Reporting by Fransiska Ninditya
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