The Labour Party's recent announcement of a proposed commuter rail network between Auckland, Hamilton, and Tauranga was notable by the level of support on show for the main opposition party.

Jacinda Ardern's only been the Labour leader for three weeks, but already she has impacted the political landscape, both nationally and in Tauranga.

Support has grown in Tauranga for Labour since Jacinda took over, with several donations and volunteers flooding in when she took the reins on August 1.

The party's policy announcement, which would enable Tauranga residents to catch the train to Auckland airport with only one change at Otahuhu, was made at the Edgewater Fan on the waterfront on Monday.

The crowd was large for mid-morning on a weekday, numbering in the low hundreds. It was a far cry from the last meeting with a Labour Party leader in Tauranga, back in March, in which the now-deposed Andrew Little spoke to a much smaller group of core supporters at the Cornerstone Pub.

Monday's audience was not only bigger, but with a greater range of people, from high school students to senior citizens, Maori and Pakeha, mothers and businessmen. There were many shades of red on display with people's outfits, and plenty of Labour placards and flags waving.

It was clear, too, from the long line for selfies following her speech, that Jacinda is well-liked. Her smile never wavered as she posed for photo after photo, and even took the time to chat with those who had something to share with her.

Labour candidate for Tauranga Jan Tinetti says the turnout was ‘phenomenal'.

'People are getting genuinely excited about the possibility of change.

'People of all ages and demographics relate to Jacinda very easily. A few people have come up to me already saying they are swapping votes to Labour.”

Jacinda also says she's ‘not bothered' by comments made by Opportunities Party leader Gareth Morgan, in which he compared her effect as leader on Labour's fortunes to ‘lipstick on a pig'.

'Everyone will make their own decisions around his comments.”

In the meantime, she's focused on winning. A recent 1 NEWS-Colmar Brunton poll put National on 44 per cent and Labour on 37 per cent, with the Greens out of parliament on 4 per cent and NZ First poised as the likely kingmakers on 10 per cent.

In the same poll, Jacinda was equal with Bill English as preferred prime minister, on 30 per cent approval.

Although world events have shown polls are not always to be believed, it is still a remarkable turnaround for a party that received barely 25 per cent of the vote in the 2014 general election.

With Peter Dunne's sudden and unexpected announcement he will no longer stand for parliament in this election, along with Metiria Turei's resignation as Green Party leader, it seems the political scalps are starting to mount up for Labour and Jacinda Ardern, who will undoubtedly benefit from both come September 23.