UPDATE
Prime Minister Scott Morrison, the MP for Cook, has told Liberal Party supporters at his election party at the Sofitel Wentworth in Sydney that he has "always believed in miracles".
"I'm standing with the three biggest miracles in my life tonight and tonight we've been delivered another one," Mr Morrison said.
"How good is Australia? And how good are Australians?
"This is the best country in the world in which to live and it is those Australians that we've been working for for the last five-and-a-half years since we came to government in 2013.
"It is those Australians that have worked hard every day, they have their dreams and their aspirations.
"To get a job, to get an apprenticeship, to start a business to start a family to buy home to work hard and provide the best you can for your kids. to save for your retirement and to ensure that when you are in your retirement you can enjoy it because you've worked hard for it.
"These are the quiet Australians who have won a great victory tonight.
"Tonight is about every single Australian who depends on their government to put them first."
On Sunday, Mr Morrison will attend church - he worships at Horizon Church, Sutherland - go to the Sharks-Manly rugby game "and, in between that, get back to work".
EARLIER
ABC chief elections analyst Antony Green believes Scott Morrison will be returned as prime minister.
"At this stage, we think the Morrison government has been re-elected," Green said on the ABC.
"We can't see an alternative to a Morrison government in the numbers we're seeing at the moment.
It seems unlikely Labor can win the 2019 federal election, barring a huge reversal of the national swing in the unprecedented number of pre-poll votes lodged, which means Scott Morrison will be returned as prime minister.
What remains is unclear is whether he will govern in minority or majority.
"We can't say whether the Government will be in a majority or minority, but we're certainly seeing enough numbers to say that the Coalition will end up with more seats than Labor," Green said.
"So, at the moment, it's looking very strongly like the Morrison government will be returned. We're just not sure in what position it will be returned.
"Will it be a majority? Will it be a minority? That's where the pre-polls will determine what happens."
The expected result is a crushing defeat for the Labor Party, which was confident it could win majority government tonight, after six years of Coalition Government and leadership instability.
The Labor Party has failed to pick up enough seats in Victoria and Western Australia to offset losses in Queensland and NSW.
The Coalition, despite a small swing against it, has at least 74 seats, meaning it is within reach of the 76 it needs to command a majority in the House of Representatives.
Labor looks to be struggling to make gains in WA while a large crossbench, which includes a number of Conservative MPs, will be enough to keep Mr Morrison in power.
This almost certainly spells the end of Bill Shorten's political career and ranks the 2019 result alongside John Hewson's 1993 loss.
Former prime minister John Howard said Mr Morrison "deserves the overwhelming gratitude of the Liberals all around the country" for his "mostly flawless" campaign.
He criticised Bill Shorten for what he described as an attempt "to divide the country along class lines".
"If you make a few bob and you are successful, and you want to invest, and you want to leave some of your children, it doesn't make you the big end of town," Mr Howard.
"He has done something I do think Bob Hawke would have ever done, and that is trying to divide the country on class lines."
Former foreign minister Julie Bishop said today's election result was "phenomenal" accomplishment by Scott Morrison.
"We were notionally 73 when we started the discussion this evening, we are now looking at 72, Ms Bishop told Channel 9.
"Labor were 72, they are now down at 59, absolute testament to Scott Morrison.
"He has run a phenomenal campaign. If he pulls this off, he will forever be immortalised."
Nine political editor Chris Uhlmann said Mr Morrison may have pulled off "one of the greatest come-from-behind victories in Australian political history".
"He will have enormous moral authority of his government," he said. "He essentially campaigned by himself."
Liberal Party faithful who went to the Sofitel Hotel in Sydney expecting a funeral tonight found themselves at a coronation.
Hundreds of diehards erupted in cheers after learning the coalition was poised to win a third term in government.
All eyes were glued to big screens in a ballroom of the as the surprise results rolled in.
"This is massive," one shocked supporter said.
"The party should build [Scott Morrison] a monument."