Malaysia's ruling alliance Pakatan Harapan led by Prime Minister Mahathir Mohamad has a comfortable majority in Parliament with 139 MPs, including 10 seats from allies in the north-eastern state of Sabah in Borneo.
The opposition consists of Umno-led Barisan Nasional (BN), former BN parties which left the coalition after it lost last year's election, as well as 18 MPs from Parti Islam SeMalaysia.
But as various players canvass for support ahead of the promised transfer of power from Tun Dr Mahathir to Datuk Seri Anwar Ibrahim, the latter could face a no-confidence vote in Parliament that would deny him the premiership, if he has not secured the necessary support.
Based on various political sources, The Straits Times estimates that Mr Anwar, the Parti Keadilan Rakyat president, has secured 75 MPs, just over half the current government's strength.
But that is nearly 40 MPs short of the minimum 112 needed for a parliamentary majority.
The House has a total of 222 lawmakers.
There is a pool of some 50 MPs who are undecided, and how they swing will determine whether, after two decades of leading the opposition, Mr Anwar will finally be Malaysia's premier.