Spending disclosures on the NSW Electoral Commission website show the Liberals forked out $120,000 on Jaimie Abbott's campaign to unseat Labor MP Kate Washington in Port Stephens.

Ms Washington spent $40,000, including $23,000 on advertising and $6000 on election materials, but retained the seat with a swing in her favour of 1 per cent.

Ms Abbott spent $83,000 on producing and distributing election material and $38,000 on advertising,

Liberal pre-polling had shown Port Stephens, which Ms Washington held with a 4.7 per cent margin, was ready to swing back to the conservatives, but a Facebook trolling scandal marred Ms Abbott's campaign.

A Liberal insider said the party knew targeting the energetic Ms Washington was "never going to be easy" and the Hunter's "dead red seats" were a "tough" challenge.

The Liberals also spent $120,000 on Brian Perrem's campaign in the marginal Central Coast seat of The Entrance, but Labor incumbent David Mehan extended his margin by 4.8 per cent.

The Coalition outspent Labor in Hunter seats where they appeared to have little hope of victory, racking up a total bill of $493,000 to Labor's $225,000. In some cases, party headquarters muzzled young candidates for fear they would speak out of turn.

The Nationals spent $60,000 on young first-time candidate Josh Angus in Cessnock, where Clayton Barr ($16,000) was returned with a 19.3 per cent margin.

Liberal city councillor Sally Halliday spent $40,000 in Maitland, twice as much as Labor's Jenny Aitchison, who held her 13 per cent margin.

The Liberals spent $31,000 on Jennifer Barrie's effort in Charlestown, $19,000 more than MP Jodie Harrison, and $30,000 on Lindsay Paterson's tilt against independent Lake Macquarie MP Greg Piper ($29,000) and Labor's Joanne Smith ($18,000).

Wallsend MP Sonia Hornery ($12,000) enjoyed a 4.6 per cent swing and a massive 25.4 per cent margin after campaigning against another Liberal newcomer, Nick Trappett, who spent $27,000.

Yasmin Catley, the deputy leader of the Opposition, spent $11,000 defending her patch against Dean Bowman ($31,000). Her 12.8 per cent margin slipped to 10.4 per cent.

Tim Crakanthorp was the only Labor incumbent to outspend his Coalition rival, $53,000 against first-timer Blake Keating's $33,000, and secured a 10.3 per cent swing in Newcastle.

The Coalition's only sitting MP in the region, Upper Hunter Nationals representative Michael Johnsen, spent $121,000 on his campaign and retained the marginal seat with a slightly increased margin.

Labor spent $28,000 on Melanie Dagg's campaign in Upper Hunter after Martin Rush ($16,000) withdrew three months before the vote after an anonymous letter accused him of assaulting a woman, an allegation he denies.

Port Stephens

Kate Washington (Labor) $40,000

Jaimie Abbott (Lib) $120,000

Labor retain +1% swing

Newcastle

Tim Crakanthorp (Labor) $53,000

Blake Keating (Lib) $33,000

Labor retain +10.3% swing

Maitland

Jenny Aitchison (Labor) $19,000

Sally Halliday (Lib) $40,000

Labor retain -0.4% swing

Charlestown

Jodie Harrison (Labor) $12,000

Jennifer Barrie (Lib) $31,000

Labor retain -0.5% swing

Lake Macquarie

Greg Piper (Ind) $29,000

Joanne Smith (Labor) $18,000

Lindsay Paterson (Lib) $30,000

Ind retain +11.4% swing

Wallsend

Sonia Hornery (Labor) $12,000

Nick Trappett (Lib) $27,000

Labor retain +4.6% swing

Swansea

Yasmin Catley (Labor) $11,000

Dean Bowman (Lib) $31,000

Labor retain -2.4% swing

Cessnock

Clayton Barr (Labor) $16,000

Josh Angus (Nationals) $60,000

Labor retain -2.7% swing

Upper Hunter

Michael Johnsen (Nat) $121,000

Martin Rush (Labor) $16,000

Melanie Dagg (Labor) $28,000

Nats retain +0.4% swing

Source: NSW Electoral Commission.

Note: Figures rounded to nearest thousand.