With the count completed in 50 of the seat's 51 polling places, Ms Claydon was leading Liberal David Compton by 63 per cent to 37 per cent on a two-candidate preferred count.

Claiming victory with a joyful seven-minute speech at the Stag and Hunter Hotel in Mayfield, Ms Claydon paid tribute to the large army of supporters who had packed into the hotel reception room to share the victory with her.

With the 50 booths counted, Ms Claydon had 48.3 per cent of the primary vote and was hopeful of winning the seat outright, without the need to go to preferences.

Mr Compton had 29 per cent of the first preference vote, with Greens candidate John Mackenzie in third position, with 13.6 per cent of the primary vote.

Ms Claydon said voters had put health and education first as election issues.

She said the Coalition had taken voters for granted and was paying the penalty.

"It felt really good out on the booths today, and I knew Newcastle people were backing us in," Ms Claydon told the crowd.

Earlier in the evening Mr Compton acknowledged he had lost his bid and said it was "hard to be a Liberal in Newcastle".

But he said the party would continue to campaign in Newcastle and put its policies to people in an effort to make the case for change.

Reflecting on his result, Mr Mackenzie said the 13-per cent plus vote he was likely to finish with was "more than we had budgeted for but less than I had hoped for".

His party colleague Michael Osborne, in second place on the NSW Greens Senate ticket, quoted ABC pollster Anthony Green who said a Greens vote of 11.5 per cent might be enough to send Mr Osborne to Canberra.

But the time it took to count the Senate "table cloth" meant he may not know the outcome until Monday.