PHILADELPHIA (MCT) — With 2 1/2 weeks left before the voting begins, the races for the major-party presidential nominations are proceeding down similarly unfathomable paths.

For months, both contests have had a clear national front-runner, with Democrat Hillary Rodham Clinton looking stronger than Republican Rudy Giuliani.

Now, to varying degrees, each of those candidates appears to be in trouble in the early-voting states, including Iowa and New Hampshire, places that will dominate the narrative for the next month.

And both New Yorkers are banking on the larger states that loom on the not-so-distant horizon — many of them voting on Feb. 5 — for bailouts, should they prove necessary.

The question, in a year when voters in both parties seem focused on electability, is whether any candidate can absorb a series of early defeats, maintain his or her strength in subsequent contests, and emerge the winner.

The answer is of more-than-casual interest to Illinois Sen. Barack Obama, former North Carolina Sen. John Edwards, former Arkansas Gov. Mike Huckabee, former Massachusetts Gov. Mitt Romney, and the other contenders in both parties.

History is not on the side of the candidate who comes up short in the Iowa caucuses, which open the process on Jan. 3, and the New Hampshire primary, on Jan. 8.

In the past four contested nomination fights, the Iowa victor has won the prize all four times: Republican Bob Dole in 1996, Democrat Al Gore and Republican George W. Bush in 2000, and Democrat John Kerry in 2004.

During the past eight nominating cycles, only one candidate, Bill Clinton in 1992, has prevailed without winning Iowa or New Hampshire. In that year, it should be noted, the Iowa caucuses were uncontested, with Iowa Sen. Tom Harkin running as favorite son.

Then again, there's never been a campaign with 20 states voting on a single day, as happens Feb. 5. On that day, about 45 percent of all the delegates to both parties' national conventions will be chosen. So precedents might not apply.

Both Clinton, in particular, and Giuliani have enough money to keep going in the face of early setbacks. They also have comfortable leads in the polls, at least for now, in many of the big-delegate Feb. 5 states, including New Jersey, New York and California.

Adding to the volatility of the current races is the scarcity of fundamental disagreements among the candidates within each party on the major issues.

Pollsters say that pushes primary and caucus voters to concern themselves more with determining who looks as though he or she could be a winner in November. Even on the electability scale, though, the current picture seems muddled.