Entries are on a par with the corresponding time last year, when a record 2369 competed, and while online entries closed on Monday evening, late entries will be accepted until Saturday evening.
To cater for the growth of the event, a new transponder system will be used to give accurate finishing times.
This involves the wearing of a bracelet, similar to that used in the Christchurch event, which is activated by the reading of a bar code.
Among this year's entrants are two of New Zealand's promising long-distance race walkers, Kate Newitt and Daniel Lord.
The pair had hoped to race in the New Zealand road championships in Christchurch last Saturday, but the earthquake led to the event being cancelled.
Both have now put more emphasis on this Sunday's half-marathon course in an attempt to get a good race under their belts before the national long-distance race walking championships in Hastings, on October 24, at which Newitt will contest the senior women's 15km and 20km time trial, and Lord will contest the open men's 20km.
Their coach, John Henderson, expects their times to be knocked around a little, due to the undulating nature of the course, but expects Newitt to complete the 21.2km course in about 1hr 55min and Lord in about 1hr 50min.
Newitt (20), a hairdressing student, of Christchurch, holds national junior race walking records over 3km (13min 41.52sec), 5km (24min 20.26sec) and 10km (50min 15.56sec).
She set her 5km record at the world youth championships in the Czech Republic last year, when she finished 18th and sliced 44sec from her previous best.
In her first few months as a senior, and in just her third race over 20km, she recorded a personal best for the distance of 1hr 42min, failing by 3min to meet the Commonwealth Games qualifying time of 1hr 39min.
Lord (18), of Timaru, a physical of education student at the University of Otago, is the New Zealand junior record-holder for the 3km distance with a time of 12min 30.54sec and has a time of 46min 37sec for the 10km walk.
He represented New Zealand at the world cup in Mexico earlier this year but was forced to withdraw during the race because of injury. He is the New Zealand junior 3000m track, 5km and 10km road race walking champion.
An early favourite in the Moro-sponsored marathon for the open men's title is Sam Wreford (Timaru) with an estimated time of 2hr 30min.
International mountain running representative Dougal Thorburn is among the early favourites for the half-marathon.
Thorburn, who last month finished third in the national cross-country championships, won the half-marathon section two years ago in 1hr 10min 55sec and is aiming for 1hr 7min this Sunday.
