KEY POINTS:
It is a brave new world in Iowa presidential politics.
The races for the Republican and Democratic nominations here are toss-ups as voting approaches. At the same time, the effect of winning - or losing - the Iowa caucuses next year is anyone's guess.
Traditionally, Iowa is significant because it is the first vote for presidential nominees in the United States, and victory here can help give a candidate momentum in other states - and a big loss can put the brakes on a campaign.
But, the future this year is unclear: Will Iowa christen the nominees and give them steam to run the table of rapid-fire state nominating primaries? Or will the state set the stage for upsets in next-up New Hampshire five days later?
Regardless of the answer, dogfights on both sides are certain in the five weeks until Iowans form a caucus on January 3.
A poll released yesterday by the Des Moines Register shows both races in dead heats. With a 4.4 percentage point margin of error, Arkansas Governor Mike Huckabee had 29 per cent to Mitt Romney's 24 per cent and Rudy Giuliani's 13 per cent in the Republican race.
Among Democrats, Barack Obama got 28 per cent, Hillary Clinton 25 per cent and John Edwards 23 per cent. Other candidates were in single digits.
More than half of likely caucus-goers in both races say they could change their minds. A chunk are undecided. An Associated Press-Pew poll being released this week echoes the competitive situations in Iowa.
"We haven't had wide-open races on both sides for some time. This is absolutely unprecedented," said David Redlawsk, a University of Iowa political scientist.
"And the impact of Iowa is unknown because the environment we're in is different."
For one, the primary calendar is packed tight. The Iowa caucuses are January 3 and New Hampshire votes on January 8.
Several other states quickly follow. That could make it difficult for anyone knocked off in Iowa to generate momentum needed for a comeback. However, the 24-hour news cycle has intensified.
That could help Iowa losers fix their missteps. Also, a slew of Republicans and Democrats are running and poised to split the votes in a multitude of ways in Iowa and elsewhere.
The other unknowns that could further scramble the contests include the behaviour of late deciders, the impact of outside groups, the candidates' potential for unforced or forced errors, and the negative ads expected in the coming weeks. All that adds up to unpredictability - nationally and in Iowa.
On the Republican side, Romney spent nearly US$5 million on TV ads, built a superior state campaign and held 396 events in Iowa only to watch his months-long lead evaporate as Huckabee surged by consolidating the support of influential religious conservatives. If beaten in Iowa, Romney still would be able to compete in New Hampshire, where he leads in polls and has a strong campaign. But a loss would set him back severely.
In the Democratic race Clinton, the leader in national and most other state polls, is fighting to keep her aura of inevitability intact and prevent Obama or Edwards from crippling it with an Iowa victory. If Clinton loses Iowa, the senator can rely on her financial and organisational muscle.
Conversely, a clear win in Iowa could cement her front-runner status and prove difficult to beat.
- AP