Countdown to curtain raiser

This week marks the opening of a political window: a 60-day countdown until the first state caucus (Iowa) and the first primary (New Hampshire) of the 2008 presidential nomination process are likely to occur.

Although the New Hampshire and Iowa secretaries of state have yet to mark the exact dates, the major party candidates have already begun the 'bell lap' of the closest and most compelling primary race in years. Definitive judgments on the candidates' chances, in the context of particular electoral scenarios, are now permissible.

Clinton-Giuliani 'leads'

Senator Hillary Clinton and former New York Mayor Rudolph Giuliani continue to lead the Democratic and Republican contests, respectively, in the national polls -- but their chances of victory are very different. US presidential primaries are conducted on a state-by-state basis, and traditionally momentum is very important:

Clinton has commanding double-digit leads in almost all of the early states (New Hampshire, Nevada, South Carolina, Michigan and Florida). The only exception is Iowa, where her advantage is smaller (see the trend polling analysis here). However, her advantage in fundraising and among the Democratic Party establishment is such that -- like George Bush in 2000 -- she could survive an early setback. She is the odds-on favourite for the Democratic nomination.

Giuliani also has a double-digit lead in national surveys over his closest competitor, former Senator Fred Thompson. However, he did not act quickly to build strong campaign organisations in the earliest primary states. This allowed former Massachusetts Governor Mitt Romney to focus his campaign spending on these key contests, and strategically build name recognition. Now Romney has a clear lead is several of the earliest primaries, creating a serious roadblock against a Giuliani steamroller.

Nomination victory scenarios

Respected non-partisan US political analysts, such as Charlie Cook and Stuart Rothenberg, have already begun to explore victory scenarios for the various candidates. Their key points include:

Former Senator Fred Thompson's challenge is fading. He still leads in South Carolina, but has been unable to gain traction outside the South. If Romney wins in both Iowa and New Hampshire, and steals South Carolina -- where he has been gaining -- his momentum could be unstoppable.

Giuliani's national support has stabilised after steadily declining earlier in the year, and is ticking upward in New Hampshire. If he steals the state from Romney, his overall prospects would surge.

Senator Barack Obama's only chance of derailing Clinton is to pip her in Iowa and campaign furiously in New Hampshire. However, like John McCain's insurgent streak in the 2000 GOP nomination battle against Bush, even several early triumphs might not be enough to halt Clinton's victory parade.

At this point, the smart money is on Romney or Giuliani for the Republicans. Sinking Clinton would take a political-electoral typhoon.

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