Party activists in Iowa will cast the first votes of the 2000 US presidential race tonight amid clear signs that the volatile battle for the Republican nomination is being pulled to the right over the contentious issue of abortion.
Fears of a stronger-than-expected showing in tonight's Iowa caucuses by the staunch anti-abortion Republican candidates Steve Forbes, Gary Bauer and Alan Keyes forced the party frontrunner, George W Bush, to bolster his own anti-abortion stance at the weekend.
But the renewed battle for conservative support for abortion could ultimately harm Mr Bush's chances in the fight with the pro-choice Democrats later this year.
Mr Bush had been under mounting pressure from conservative Republicans to stiffen his stance on abortion as voting day neared in Iowa. This weekend he stated that the US supreme court had exceeded its constitutional authority by proclaiming a right to abortion in the 1973 Roe v Wade case, the anniversary of which yesterday was marked by anti-abortion protests in many US cities.
By saying he believed that state legislatures should have the right to determine their own abortion laws, Mr Bush was hoping to solidify his support in Iowa, where a poll this week by the Des Moines Register showed that 40% of the state's Republican voters considered themselves born-again Christians.
By emphasising the states' rights issue, Mr Bush was also looking ahead to the first post-New Hampshire primary in South Carolina, where the same issue is at boiling point over the display of the pro-slavery southern Confederacy flag.
The millionaire publisher Mr Forbes has spent more than $3m this year in Iowa in an effort to establish himself as the leading conservative alternative to Mr Bush. He describes Mr Bush as a "Johnny-come-lately to the pro-life cause" and has recently lambasted him in campaign advertisements as "a pro-life pacifist".
Unlike Mr Bush, Mr Forbes pledges to have an anti-abortion vice-presidential running mate, and to make overturning Roe v Wade a litmus test for any appointments to the supreme court that he might make as president.
Mr Bauer and Mr Keyes in turn regard Mr Forbes as less than a whole-hearted believer in the anti-abortion cause, and they are both fighting hard to capture the conservative vote in a state with powerful religious networks.
Mr Bauer mounted the most dramatic anti-abortion campaign event of a highly charged weekend by visiting the grave of a foetus in a Des Moines cemetery to commemorate the Roe v Wade decision.
"We have taken a whole class of Americans - our unborn children - and said to them they have no rights," Mr Bauer said after laying two roses on the grave. "We treat our own flesh and blood like styro-foam cups. If we can't get this issue right, we're not going to get any of them right."
No one, including his opponents, expects Mr Bush to do anything except win tonight's Republican caucuses in the predominantly conservative plains state. But in a contest where the media's portrayal of the candidates' showings is at least as important as the actual result, the Bush campaign is now trying to dampen earlier expectations of a record win.
Mr Bush's conservative opponents have gambled most of their time and money on a strong showing in tonight's Iowa contest, hoping for a boost which will carry through to the February 1 primary in New Hampshire.
The most recent Iowa polls have suggested Mr Forbes, in particular, is building a late surge of support, which threatens to keep Mr Bush's vote tonight under 50%. Any lesser showing would risk being seen as a defeat in the all-important expectations game.
The danger from Mr Bush's perspective is that he could become the victim of a pincer movement by his opponents, with the conservatives wounding him in Iowa, and Senator John McCain, who is not competing in Iowa, then defeating him from the left in New Hampshire. Current polls put Mr McCain six points ahead of Mr Bush in the New Hampshire contest.
The wider problem for the Republican favourite is that too many concessions to the right in the race for the party nomination may come back to plague him in the presidential contest itself. A new Gallup poll shows that abortion ranks 19th out of 25 issues in importance to US voters and is seen as "extremely important" by only one in five Americans.
How the caucus works
The caucus is a form of decision making that was once commonplace in US politics but which has now been largely replaced by the system of primaries, such as that which begins in New Hampshire next week.
In contrast to the primaries - in which registered supporters vote in secret in polling booths - the caucuses are the domain of party activists and well-organised (for which, read well-financed) candidates.
In Iowa tonight each of the 2,100 state precincts (roughly equivalent to a British electoral ward) will hold party meetings.
Recent experience suggests that approximately 10% of Iowa's 1.8m, overwhelmingly white, registered voters will answer the call and brave the winter weather to turn out tonight.
Since there is a contest in both the Democratic and Republican parties this year, candidate turnout is likely to be split fairly evenly between the two parallel state elections.
Voting at the caucus meetings is normally effected by a show of hands, which are then totalled up state-wide.
On the Republican side, the result is a straight count of heads for each candidate.
The Democrats, by contrast, require each caucus to divide up the votes among candidates with at least 15% support at each meeting.
