New Zealand punters have poured their cash into locally owned Who Shot Thebarman to win Tuesday's Melbourne Cup.

For the fourth consecutive year there are no horses trained in New Zealand in the race that stops two nations.

But this year two horses which were trained on the other side of the Tasman 12 months ago are well-supported in the market.

Lucia Valentina is second favourite at $6.50 after finishing third in the Caulfield Cup to Admire Rakti, the Japanese-trained $4.80 favourite for Tuesday's 3200m contest.

But the TAB's biggest bets have been on Auckland Cup winner Who Shot Thebarman, owned by the O'Leary brothers.

NZ TAB executive general manager Glenn Patrick says about $500,000 has already been bet by Kiwi punters on Who Shot Thebarman, who won the Auckland Cup in March when trained by Mark Oulaghan before moving to the Sydney stable of expat Kiwi Chris Waller.

"Increasingly non-traditional customers are punting on the Melbourne Cup so naturally people tend to get a bit patriotic about it and interestingly our seasoned punters do too," Patrick said.

"This year we are seeing early bets favouring Who Shot Thebarman over preferred second favourite Lucia Valentina, and quite a few for outright favourite Admire Rakti. But as the race approaches we are expecting to see more punters come out in support for Lucia Valentina."

Who Shot Thebarman is a $17.80 chance in the NZ TAB fixed odds market but is much shorter on the tote at $6.80.

Lucia Valentina, owned by Wellington businessman Lib Petagna, was trained by Stephen Marsh when she won the Group Three Eulogy Stakes at Awapuni in December but was transferred early this year to Kris Lees, who trains in the NSW city of Newcastle.

Lees has trained her to two Group One wins.

New Zealand-bred horses dominated Melbourne Cup fields from the 1950s to the 1980s but there are just five runners with the NZ suffix in this year's race - Who Shot Thebarman, Lucia Valentina, Precedence (an $81 shot), Brambles ($35) and Mr O'Ceirin ($201).

New Zealanders bet $9.3 million with the NZ TAB on last year's race.