OTTAWA - The NDP leadership race has been criticized as boring but behind the scenes ... it's just as dull.

There's been much speculation about second-ballot strategies and secret deals being hatched to enable a dark horse to stage a come-from-behind upset of the perceived front-runners.

Comparisons have been made to the 2006 Liberal leadership contest, in which the third-place Stephane Dion came up the middle to beat Michael Ignatieff and Bob Rae.

But the truth is, the one-member, one-vote process being used by the NDP to select a successor to the late Jack Layton is entirely different than the delegate convention process that produced Dion. And it's much harder to manipulate.

In 2006, Liberal delegates were elected in their ridings to support specific candidates on the first ballot at the convention. As the last-place contender withdrew on successive ballots, they made a big show of crossing the floor to throw their support to a rival, taking most, if not all, their delegates with them.

The clincher for Dion was a secret pact with Gerard Kennedy, who wound up finishing fourth. Before the first vote was cast, the two had agreed that whichever one of them was dropped off the ballot first would throw his support to the other. Kennedy delivered almost all his delegates to Dion, vaulting him past Rae and Ignatieff.

There's little chance of a similar deal working in the NDP contest.

For starters, there will be no delegates at the March 23-24 convention in Toronto. Instead, anyone who takes out a membership by Feb. 18 is eligible to vote.

More than 2,000 New Democrats are expected to attend the convention -- a record turnout for the NDP --and they'll cast their ballots there. But the vast majority of the party's more than 100,000 members will vote by mail or through the Internet, using preferential ballots to mark their first, second and subsequent choices.

If a member's first choice is dropped off the ballot, their second choice will be counted and then their third and so on until one of the seven candidate emerges with more than 50 per cent of the votes.

Members will be able to begin voting online or by mail as of March 1. Most will have voted long before March 24.

So, while trailing candidates may still make a show of crossing the floor at the convention, their supporters will have long since determined their second choices.

A candidate could still conceivably cut a deal with a rival, in which each agreed to urge their supporters to mark the other as their second choice. But they'd have to do it before March 1 and word would almost certainly leak out, risking a backlash among supporters of the other five candidates.

Hence, the safer strategy -- and the one that appears to have been adopted by all seven contenders thus far -- is to court the supporters of all rival candidates, to be everyone's second choice. And that means playing nice behind the scenes as much as in the public eye.

"You play to your strengths and you play to as many people as possible and aligning yourself with one (rival camp) might alienate others," says Joe Cressy, spokesman for Ottawa MP Paul Dewar's campaign.

Indeed, he says a candidate could alienate his own supporters if he or she were to try to direct them on their second choices.

"At our core, we're an anti-establishment party ... People don't like being told what to do. It comes off smelling bad."

Although there is no accurate way to measure support, Dewar, Montreal MP Thomas Mulcair, former party president Brian Topp and Toronto MP Peggy Nash are widely perceived to be in the top tier of candidates. British Columbia MP Nathan Cullen, Manitoba MP Niki Ashton and Nova Scotia pharmacist Martin Singh are seen to be in the lower tier, although Cullen has performed well and is thought to have momentum.

Cullen says none of the presumed frontrunners has tried to cut a deal with him. Nor is he interested in indulging in machinations that might enable him to run up the middle.

"I've told my campaign, we stay straight, we're going where we're going and it'll be what it'll be."

Other camps agree they've seen no sign so far of any second-choice deals being struck or even attempted.

During leadership debates, Cullen notes that other candidates will sometimes "throw someone else a bone," offering praise for a rival in an apparent bid to woo second-choice support. But that's about the extent of it.

For his part, Cullen shuns even that degree of strategizing.

"I find it distracting. It changes the way you act, it changes the things you say. I just want to be who I am and want to say the things that I want to say. I think when you start to get into the deal making, it starts to shift that."