A Mercury analysis of figures from the November 2016 byelection for the seat of Wollongong show Labor's Paul Scully outspent his independent rival sevenfold.

Labor spent $280,000 on Mr Scully's campaign compared with the $41,000 spent by Cr Bradbery, the city's Lord Mayor.

Mr Scully received 46.5 per cent of total first preference votes, to Cr Bradbery's 33 per cent.

On a two-candidate basis after preferences had been distributed, Mr Scully won with 58 per cent to Cr Bradbery's 42 per cent.

It was hardly the cliffhanger of 2011, when Labor's Noreen Hay held off Cr Bradbery by 682 votes after preferences.

But given their respective advertising budgets, the relative closeness of the election shows the scale of Cr Bradbery's achievement in making it a contest. Wollongong is heartland Labor, and the party was determined not to let the seat slip.

"As I said at the time I was announced as the candidate [that] I would take it seriously, and I did," Mr Scully told the Mercury.

"Wollongong is an important seat to Labor; always had been."

NSW Electoral Commission disclosures show that of Mr Scully's $281,000, about $12,000 was from reportable political donations - led by $2600 from accounting firm Ernst & Young, $2160 from the Maritime Union of Australia, and almost $1700 from Cunningham MP Sharon Bird.

More than $30,000 was raised from Labor fundraising events, including an evening with Wayne Swan at Ernst & Young in Sydney, and he received $28,000 in donations that were smaller than the threshold for mandatory reporting.

This enabled the Scully camp to spend more than $35,000 on campaign strategists, $27,000 on polling and research, and $221,000 on communications, including advertising in print, radio, television and online.

The vast share was paid for by the Labor party.

"It's also the case that it's a byelection, and in byelections you have additional expenditure ... to make people aware of it that it's actually on," Mr Scully said.

"What's not reflected in the expenditure report is ... the three pairs of shoes I went through doorknocking, the few kilos I lost in weight, and the 13 weeks I dedicated to exactly those tasks."

Of Cr Bradbery's $41,000, $16,071 was contributed from his own pocket, and $12,700 came from donations.

"Put it like this - the Labor Party wasn't going to lose that seat," Cr Bradbery said.

"The amount of advertising was phenomenal. That was a by-election and the whole Labor machine could focus on it.

"You can't compete with that. Not if you're an individual - or if you're an independent. I was very fortunate to be able to mobilise the $41,000 ... and I put in a fair slab of my own money."

His largest donor was Wollongong businessman Lube Markovski, whose company Wealthmade Pty Ltd (owner of the Wollongong Grill'd burger franchise) gave $2600.

Wollongong company Central Data Networks, which donated against Cr Bradbery at a council level, gave $2600 to his state campaign.

Also there for Cr Bradbery was Omar Mosque chairman Munir Hussain - the Islamic leader donated $2500 towards the Uniting Church minister's election effort.

Cr Bradbery said this was "because I had a very good relationship with the Islamic community at the time".

Christian Democratic Party candidate Colleen Baxter spent more than $15,600 campaigning and received 3.5 per cent of first preferences, while Greens candidate Cath Blakey spend not a cent in the by-election and received 10.3 per cent.

Disclosure details are not yet available for the March state election.

Cr Bradbery spent less than half in 2016 than he did in the the 2011 election. That time, he dropped $90,000 battling Ms Hay, who spent about $102,000, with the largest expenses being printed materials and distribution. Liberal Michelle Blicavs spent $47,000.

Funeral director Alan Parsons was the Wollongong area's biggest third-party political donor at the 2017 city council elections, giving $2000 to Gordon Bradbery's successful campaign.

But the biggest spender in the council campaign was Cr Bradbery himself, who stumped up $11,000 to fund his team of candidates in the September 2017 poll.

Cr Bradbery's contribution was the lion's share of his Ward 3 team's costs - a campaign which got NSW Ports executive Dom Figliomeni elected to council, as well as the team leader returned to the city's top job.

There were another seven donors who gave less than the reportable limit of $1000 to the Bradbery group. Most of the team's money raised was spent on radio advertising.

Mr Parsons' donation was notable because of the controversy over his new new crematorium at Unanderra, which was approved by Wollongong's Independent Hearing and Assessment Panel despite 26 objections from the public and neighbouring business owners.

The panel is independent of council. Council's planning staff had recommended it for approval.

Council closed down its own crematorium in 2018, predicting it would make a loss after the new Parsons venue was operational.

Cr Bradbery, who as a Uniting Church minister does some work as a funeral celebrant, has worked on funerals with Parsons - as well as other funeral providers.

He said his relationship with Mr Parsons had no influence on any decisions over the crematorium. There is no suggestion otherwise.

Cr Bradbery said he had a conflict, so removed himself from any council debates on the crematorium issue.

"I declared a conflict of interest and got out of that meeting," he said.

"Anything involving Wollongong crematorium and its future involved a declaration of a conflict of interest."

The council had made several attempts to shut down its ageing cremator over the previous decade, largely owing to the high cost of equipment upgrades.

An attempt was made by the Greens and Port Kembla's Tender Funerals to find another operator but it was voted down in council.

The 2017 Wollongong City Council election featured a $2000 donation from the Parramatta-based NSW Transport Workers Union branch.

The TWU gave the money Labor's Janice Kershaw group in Ward 1, while the Thirroul branch of the ALP gave them $1822 from a fundraising dinner.

Disclosure documents filed with the NSW Electoral Commission show that apart from the union donation, party functions and self-funding were the favoured way for Labor to raise funds.

Labor's Ward 1 team got Crs Kershaw and Jenelle Rimmer elected. It spent more than $8000, $4100 of which had been donated by Cr Kershaw, $610 which came from Cr Rimmer.

Ward 2 Councillor David Brown gave $1500 to the Labor campaign. A trivia night fundraiser for his mayoral campaign raised $650, while a fundraising lunch by M2 Kitchen raised him $4055.

Also in Labor, Vicky King and Chris Connor each donated $2280 to their Ward 3 group's campaign, while Ann Martin gave $500. Cr King chipped in another $1000 for her own campaign.

Labor councillor Tania Brown donated $1700 to the campaign.

Also ringing the registers was Liberal councillor Cameron Walters, who was given $2000 from a family member, and $1000 from Wollongong company Central Data Networks.

He gave $3700 to the Liberal Party, and raised $3500 at a fundraising dinner featuring Mr Ward and Member for Hornsby Matt Kean.

Greens candidates declared no donations received and no expenditure.

For those without party machinery, raising and spending money was harder.

Regular Ward 2 independent candidate Andrew Anthony spent $4187 on his group's campaign, which featured four candidates running in the same ward. None were successful.