Like the Democratic race four years ago, the 2008 Republican presidential contest is proving tough to figure. Each time one candidate seems to gain an advantage, something happens to lower his standing and elevate a rival.
The hottest current contender, former Sen. Fred Thompson, hasn't even entered the race yet.
And calculations are complicated by the different strategies candidates have for next year's primaries and caucuses. The only certainty is that they can't all be right.
Take their differing approaches to Iowa, whose January caucuses will be the initial test. Three of the four top contenders are bypassing the Aug. 11 Ames straw poll, where the contest to muster the most party activists has defined recent GOP races.
With former New York Mayor Rudy Giuliani and Sen. John McCain opting out, and Mr. Thompson delaying his announcement decision, former Massachusetts Gov. Mitt Romney is the only participant among GOP front-runners. That gives a chance for darker horses like Sen. Sam Brownback of Kansas and former Govs. Mike Huckabee of Arkansas and Tommy Thompson of Wisconsin to make a showing.
Romney, fourth in most national polls, hopes an Iowa win will catapult him to a second triumph eight days later in New Hampshire. That's how two former Massachusetts candidates won their party's nomination: Sen. John Kerry won both in 2004, and Gov. Michael Dukakis combined a strong third in Iowa and a victory in New Hampshire in 1988.
But this race will move more quickly from Iowa and New Hampshire to big states with large delegate prizes. Romney's rivals are betting a changed calendar will mean a changed dynamic.
For instance, Giuliani insists he has not abandoned Iowa, where he campaigned last week, or New Hampshire. But he is targeting the Jan. 29 Florida primary and such key Feb. 5 states as New York, New Jersey and California.
The polls show why. Giuliani leads nationally as well as in all four of those big states. The question is whether he can maintain his advantage if one or more rivals gets a publicity bonanza from victory in Iowa, New Hampshire or both.
Giuliani's hopes might depend on how many rivals remain viable Feb. 5. As the least conservative of the four top candidates, he gains the most if the votes of the conservative faction are split.
Many Republicans dismiss his chances because they figure the race will come down to one conservative and Giuliani, which they presume would favor the conservative.
Romney's path to become that conservative is clear. McCain's or Thompson's is harder to discern.
McCain, seeking to offset speculation that his fundraising and organizational problems doom his candidacy, has vowed to stress Iowa, New Hampshire and the early February South Carolina primary. But the Arizona senator has a lot to overcome in Iowa. In 2000, he bypassed its caucuses, which didn't sit well with Iowans, though he has abandoned his prior opposition to ethanol subsidies.
And while his best hope remains New Hampshire, he will be hard-pressed to match his 2000 victory there, in part because most independents - a key source of his strength in 2000 - are expected to vote in the Democratic primary.
Thompson has reached second place in many polls without becoming an active candidate, attracting Republicans unenthused about the field. Sooner or later, None of the Above will become One of the Above. Then, we'll learn if the reality is as good as the promise.
His late start could handicap him in both Iowa and New Hampshire, but he'll have an advantage in South Carolina as the only Southerner among the top four.
Only in February will we know who figured out the best way to play the game.
Carl P. Leubsdorf, Washington, D.C., bureau chief of the Dallas Morning News, can be reached at firstname.lastname@example.org.