"There are many challenges facing Bersatu, especially with the opposition disunited," said Norshahril Saat, fellow at the ISEAS Yusof-Ishak Institute, a research group specializing in Southeast Asian studies.
There are already a number of opposition parties to BN, including the People's Justice Party (PKR), Democratic Action Party (DAP), the Pan-Malaysian Islamic Party (PAS) and Parti Amanah Negara (Amanah). But infighting between these groups has only solidified the BN's grip over the country, Saat noted.
Certain members of PAS left to form Amanah in 2015, uniting with the PKR and DAP to form an opposition alliance called Pakatan Harapan. However, the alliance has already lost two by-elections to BN this year. Meanwhile, other smaller opposition vehicles have united to form another pact called Saksama.
Bersatu has said that it will ally with Pakatan Harapan but if that materializes, it's expected to only muddle the opposition landscape further, noted Oh.
Still, it will certainly make the 2018 elections interesting, said Saat. "Mahathir's hope is that sentiment against the BN government has not changed since 2013, when more than half of Malaysians voted for the opposition."
With a lack of viable alternatives to Najib and slowing economic growth, Malaysia overall is in a state of "strategic survival," said Nguyen.
Amid a messy political atmosphere, there is an air of stagnation around the country's medium-term outlook and a lack of debate about how to take Malaysia to the next level of development, she explained.
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