Dr Mike Freelander is the Macarthur MP once again with the incumbent declaring victory in a live video on his Facebook page tonight.
Dr Freelander will head into his second term with 59.21 per cent of the two-party preferred vote and 49.67 per cent of the primary vote, according to Australian Electoral Commission figures at 9.45pm on Saturday, May 18.
The figures are based on 48.01 per cent of votes cast today, from 38 of 50 polling places.
"I am very humbled that the people of Macarthur have put their faith in me and in the Labor Party," Dr Freelander said in his Facebook video tonight.
"I'm pleased to inform you that my main rival in the campaign, Riley Munro, has called me tonight to concede defeat and we have declared victory in the seat of Macarthur.
"I am very humbled that the people of Macarthur have entrusted me with being their representative."
Dr Freelander said he was greatly disappointed that the national votes suggested Labor would not be forming government in 2019.
However, he was pleased that his party had won polling stations in Leppington, Oran Park and Gregory Hills, and performed "extraordinarily well" in Rosemeadow and Minto.
He thanked his team for all their hard work during the campaign.
"I put the victory down to a number of things, but predominantly it's due to my team," he said.
"Most of them are very young but show a maturity beyond their years."
Macarthur voters flocked in their thousands to polling booths across Campbelltown and Camden today to cast their vote in the federal election.
There were seven candidates fighting to take out the top spot on ballot papers, from a variety of parties.
Incumbent MP Dr Freelander was considered the favourite to retain the seat - which stretches from Minto Heights to Menangle Park, Wedderburn to Rossmore - after a strong victory in the 2016 election.
Dr Freelander attracted 51.9 per cent of the primary vote in the previous election, unseating the then-Liberal MP Russell Matheson.
Other candidates in this election were Riley Munro (Liberal), Jayden Rivera (Greens), James Gent (Christian Democrats), Matthew Stellino (Animal Justice Party), Nathan Murphy (United Australia Party) and Shane Norman (One Nation).
The Advertiser visited several Campbelltown polling booths today and was surprised to see zero Liberal volunteers handing out flyers, and very little Coalition signage.
Folks in the camps of Dr Freelander and Mr Munro would have been starting to sweat when eight per cent of the vote was counted, with the ABC placing the Labor MP ahead by only 0.6 per cent of the two-party preferred vote.
The rest of the night saw Dr Freelander's two-party lead extend further.
The incumbent's swing was significantly smaller than the last election, where the paediatrician achieved an 11 per cent swing in his party's favour. At last count, Dr Freelander's swing was just 1.18 per cent this year.
Mr Munro received the next biggest slice of primary votes behind Dr Freelander, with about 30 per cent of the first preference count.
One Nation's Mr Norman - who failed to respond to the Advertiser's request for comment or photographs throughout the campaign - was next, picking up just ove reight per cent of the vote.
They were followed by Mr Rivera, Mr Gent, Mr Murphy and Mr Stellino, respectively.
Informal votes made up almost 10 per cent of all votes counted in Macarthur on election day.