* Morrison defies odds to score improbable election win
* Labor shattered, challengers line up for leadership
* Coalition on track for outright majority
* Jubilant prime minister attends Sunday church service
* Challenge from far right parties largely falls flat (Adds Morrison's appearance at football match, Ardern quote, paragraphs 5, 10)
By Lidia Kelly and Jonathan Barrett
MELBOURNE/SYDNEY, May 19 (Reuters) - Australian Prime Minister Scott Morrison thanked his fellow Pentecostal churchgoers on Sunday after a miraculous election victory that defied years of unfavorable opinion polls and bruised a Labor opposition that had been widely expected to win.
Morrison's Liberal-led conservative coalition has won or is leading in 76 seats, the number needed to form a majority government, according to the Australian Electoral Commission. Slightly more than three-quarters of the roughly 17 million votes have been counted.
A jubilant Morrison hugged community members after an early Sunday service at the Horizon Church in Sydney's southern suburbs, from where he was first elected to parliament in 2007.
"You don't get to be a prime minister and serve in that capacity unless you first are a member of your local electorate," he said.
He drew cheers later on Sunday when he arrived in the stands to watch his team, the Cronulla Sharks, in a rugby league match in his beachside electorate.
Morrison told raucous supporters late on Saturday, who had earlier seemed resigned to defeat, that he had always believed in miracles.
The result drew comparisons with Republican Donald Trump's victory over Democratic rival Hillary Clinton in the 2016 U.S. presidential election.
Trump and Israeli Prime Minister Benjamin Netanyahu were among the first world leaders to congratulate Morrison.
"Congratulations to Scott on a GREAT WIN," Trump said on Twitter before calling the Australian leader..
Jacinda Ardern, the progressive prime minister of neighbouring New Zealand, also called to congratulate him, saying that Morrison "understands us".
Opinion polls in Australia had all pointed to a Labor victory. So strong was the expectation the government would fall that one betting agency even paid out bets on a Labor win days before the election.
Morrison, who emerged as an unlikely leader after Liberal party infighting last year, cast himself as the candidate who would work for aspirational voters and the tactic seemed to strike a chord.
PAINFUL LABOR LOSS
If the coalition fails to secure at least 76 seats, it will need to rely on support from independent politicians, such as maverick conservative Bob Katter, or small parties to govern.