There are two key reasons why Barisan Nasional (BN) cannot afford to lose Johor - Umno was born in the state soon after World War II, and it is also a stronghold of the Malaysian Chinese Association (MCA), the second-biggest component party of the BN.
And that is why the opposition is targeting the state as a rich prize.
For Umno's 3.2 million members, Johor is not like the other 12 states but a fortress tied to its proud history of pushing for Malaysia's independence. The United Malays National Organisation was born 71 years ago in 1946, with its founder Onn Jaafar a Johorean.
"(The opposition) is using Johor as a symbol of a Malaysian revival, because Umno was founded in Johor and the state has always been a bastion of Umno, so if there is political change, it should also come from Johor," said Dr Norshahril Saat, a fellow at ISEAS - Yusof Ishak Institute.
Johor, too, is an anchor state for the MCA. The Chinese party is the most important component of the 13-party BN after Umno, representing ethnic Malaysian Chinese who form 23.2 per cent of the country's 32 million population.
The MCA contested 37 parliamentary seats in the 2013 elections and won only seven. Crucially though, four of the seven seats it secured were in Johor.
The party has typically won the most seats in the state, and a string of recent party chiefs - Tun Dr Ling Liong Sik, Tan Sri Ong Ka Ting and Datuk Seri Chua Soi Lek - represented Johor constituencies.
But opposition leaders say that despite BN's rich history and ties to Johor, things have changed. They say that, like in other parts of Malaysia, the default loyalty to the ruling coalition is less clear-cut today because of roiling political and financial scandals over the decades. The advent of social media has also now spread to the rural areas, they add.
Take Mr Nasir Rais, 47, a contractor who voted for BN in 2013. He has said that he will now vote for Pakatan Harapan (PH), the four-party opposition alliance.
Asked why, the resident of Skudai, a district in Johor Baru, said: "Honesty and a clean government are very important. Cost of living now is also going up, the same amount of money can buy fewer things (compared with) last time."
The shift away from BN in Johor is clearly evident, judging by the rising number of opposition seats in the state legislature in the last three general elections.
The opposition now controls 19 wards in the 56-seat assembly.
They had none after the 1999 elections, secured one in 2004 and then won six in the 2008 polls. Additionally, a significant number of the state legislature seats, or 20 of the 56 wards, were eventually decided with a slim majority of under 5 percentage points in 2013.
Eight of these seats are held by parties in the opposition PH alliance. One is held by the Umno-friendly opposition Parti Islam SeMalaysia (PAS), and 11 are BN seats, said Dr Francis Hutchinson, coordinator of the Malaysia Studies Programme at ISEAS - Yusof Ishak Institute.
"This indicates that Pakatan Harapan has some fertile ground for further expansion," he said. PH comprises the Chinese-based Democratic Action Party, the multi-racial Parti Keadilan Rakyat, Parti Amanah created by disgruntled PAS members, and the recently formed Parti Pribumi Bersatu Malaysia (PPBM) led by former premier Mahathir Mohamed and former deputy prime minister Muhyiddin Yassin.
A long-time Johorean politician, Tan Sri Muhyiddin, who is now a PH leader, said the opposition has been well received as he toured the state, including in Felda palm plantations that used to be off-limits to the opposition because their settlers were a solid vote bank for Umno.
"If you see the result of the 2013 election, we have 19 state seats under the opposition. Johor has 56, so you need only 10 to change the government," Mr Muhyiddin told The Straits Times in a recent interview. "They (BN) are shaking to the very core at what is happening now."
The opposition claims Johor, like other states, will witness a "Malay tsunami" at the next polls - a huge wave of Malay voters who will switch to the opposition.
But Deputy Home Minister Nur Jazlan Mohamed, who is also a Johor MP, has dismissed the opposition claims, saying they were intended to stop ethnic Chinese voters from running away from the PH.
"The opposition has no choice but to speak about the Malay tsunami because the Chinese are fed up with them and are going to abstain in the next general election," Datuk Nur Jazlan told The Straits Times.
He said the key concerns for Johor voters remain the cost of living and the high cost of housing, the same bugbears keenly felt by most Malaysians.
Some political observers agree that the opposition claims ought to be taken with a pinch of salt as the constant bickering within their ranks has led to political exhaustion and cynicism. Some voters also remain wary about Tun Dr Mahathir's role as opposition chief because they see him as someone who is keen only to oust Prime Minister Najib Razak and will not embark on reforms.
On the economic front, Johor continues to bank on its location next to Singapore. Johor's economy is expected to grow by more than 5 per cent again this year, slightly better than the national gross domestic product, and skylines of many cities and towns from Johor Baru and Kluang to Pagoh have become more impressive.
Of the 26.8 million visitors to Malaysia last year, nearly half, or 13.3 million, were from Singapore and most of them passed through Johor. Dozens of construction cranes in southern Johor's Iskandar Malaysia region reflect a housing boom led by developers from China. And helping to boost trade is Johor's position as the only Malaysian state with two major ports, Tanjung Pelepas and Johor Port.
"We are fortunate to live in a state with a strong economy. Things could be better but that is not a reason to vote against BN," said Kluang town resident, retiree Johari Kassim.
Still, some want a government that is more responsive to their needs. "We just want a fair, transparent and meritocratic government," said Johor hawker Patrick Wong, 50.
"At least I want to let Umno know that the people are unhappy. They were born here so if they lose Johor, it will be a sign for all Malaysia."