"It will make the Rotorua electorate tougher for Labour, but we take the electorate very seriously and are confident we will have a strong candidate for the next election.
"We had a meeting with party members and activists from all over the Bay last weekend to plan our election campaign and candidate selections are getting under way.
"The important thing is that under MMP it's the party vote that changes the government. We obviously want to win the seat, but it's the party vote that really counts," Mr Twyford said.
Under the changes, boundaries will not be changed for the seven Maori electorates or for the Taupo electorate.
Each electorate must have approximately the same number of people to ensure equal representation. The average electoral population will be 59,731 people for North Island general electorates, 59,679 people for South Island general electorates and 60,141 people for Maori electorates.
There will be 64 general electorates and seven Maori electorates for the 2014 and 2017 general elections.
The Rotorua electorate would pick up about 9900 voters from the Bay of Plenty electorate and lose about 9400 to the East Coast electorate.
People have until December 23 to object to any of the changes with public hearings set down for mid-April next year.
Rotorua MP Todd McClay said he would receive a "paper increase" to his majority, from about 7300 after the last election, to between 8000-8500 votes.
"I was expecting there would be some changes made," he said.
"I've had an office in Te Puke with Tony Ryall for the last five years and I'm looking forward to working with the wider Te Puke area. But, for me, Rotorua is the heart of the electorate and is where I live with my wife and family."
