Malaysian Prime Minister Najib Razak and his deputy Muhyiddin Yassin will remain Umno's party president and deputy president respectively, but all the remaining leadership roles in the party will be hotly contested in elections next month.
There are six in the race for the three vice-presidential posts, four willing to take on Umno's youth wing chief and three vying to head Wanita, the women's wing, ensuring that the polls on Oct 12 and 19 may be the most closely watched ever.
After Datuk Seri Najib's party suffered a drubbing in the May general elections, there were rumblings that former premier Mahathir Mohamad, who continues to wield influence, might back a challenger for the presidency.
That did not come to pass and Umno secretary-general Tengku Adnan Tengku Mansor pointed out that the absence of contenders was a vote of confidence in the party leadership.
"This shows that Umno has matured, Umno is strong and they believe that two leaders can lead the party and the country," he said at a press conference at the close of nominations for party posts on Saturday.
However, all eyes are on Datuk Mukhriz Mahathir, the youngest son of Tun Dr Mahathir, to see whether he will manage to oust one of the incumbent vice-presidents who include Mr Najib's cousin, Datuk Seri Hishammuddin Hussein.
As vice-president, Mr Mukhriz could become deputy prime minister in the next few years.
The others running for vice-president are Datuk Seri Mohd Shafie Apdal and Datuk Seri Ahmad Zahid Hamidi, as well as two senior politicians, Tan Sri Isa Abdul Samad and Datuk Seri Mohd Ali Rustam.
Dr Mahathir's grassroots supporters are likely to favour Mr Mukhriz, which means he could upset Mr Najib's current leadership line-up.
Ahead of his nomination, Mr Mukhriz told Malaysia's Berita Harian, a Malay language daily, in an interview published on Saturday: "If we want transformation, we need to have the courage to do it." But he has denied that he is trying to build on his father's legacy in Umno.
As interesting as the fight for the vice-presidential posts is the five-way fight for the Youth Chief post.
Mr Akhramsyah Muammar Ubaidah Sanusi, Mr Karim Ali, Mr Irwan Ambak and Mr Syed Rosli Syed Harman Jamalullail are challenging the incumbent, Mr Khairy Jamaluddin.
Mr Akhramsyah is the son of former Kedah Menteri Besar Sanusi Junid, who is also known to be aligned with Dr Mahathir.
A multi-cornered fight may not jeopardise Mr Khairy's chances, analysts say, because he retains influence as a minister.
Former Cabinet minister Shahrizat Abdul Jalil is defending her Umno Women's Chief post which she has held since 2009. She was recently appointed by Mr Najib as special adviser on women's affairs with the rank of a minister, seen as a tacit support to defend the post.
Datuk Shahrizat will be challenged by Ms Raihan Suleiman Palestin, a lawyer, and Datuk Maznah Mazlan, a former deputy minister, who turned up at the nomination centre 15 minutes before it closed.
Ms Jamilah Hanim Othman, an executive committee member, and Ms Mas Ermieyati Samsudin, a Member of Parliament, are vying to be Puteri Umno chief. Incumbent Rosnah Rashid Shirlin will step down as she has passed the leadership age limit of 40.
This year's Umno elections are also set to be the most democratic ever. The contests will be carried out under Umno's new voting system involving nearly 150,000 members at its 191 divisions. Previously, a smaller number - 2,500 delegates - at the party's central meeting voted in the leaders.
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