With the country preparing to inaugurate Barack Obama as the next president of the United States next month, it’s hard to remember how improbable the notion of a President Obama seemed just a year ago. In fact, all indications are that Obama himself wasn’t really expecting to win it all in 2008.

After all, when he announced his candidacy, the conventional wisdom saw former First Lady and New York Senator Hillary Clinton as the prohibitive front-runner. The vaunted Clinton political machine was supposed to be unbeatable in Democratic Party competitions. But behind the scenes there were definitely rumblings of "anybody but Clinton."

Then, in the first quarter of last year, Obama and his team stunned the political world with a then-staggering fundraising total of $26 million. Obama and Clinton were essentially even in the money competition at that point, leaving the rest of the Democratic field in the dust. In April 2007, for the first time, Obama pulled even nationally with Clinton among Democratic primary voters. By the end of the month, Obama even inched ahead, leading Cliinton 32% to 30%. That was the first poll anywhere to show Obama ahead nationally. It was also the last one for months.

The first of countless debates was held in early May, and that was a forum where Obama struggled in the early going. Once the debates began, Clinton gradually expanded her lead week after week, month after month. The Clinton swagger and sense of inevitability returned.

Then came an October debate in Philadelphia in which Clinton couldn’t figure out how to answer a question about drivers’ licenses for illegal immigrants. For the first time since April, her lead was dented. At Rasmussen Reports, we defined the race as a Tale of Two Narratives. “In one narrative, New York Senator Hillary Clinton has lost support due to her debate gaffe and follow-up efforts. The other is that Clinton is the dominant front-runner with significant leads just about everywhere. Both have the virtue of being true.”

We also noted that “the place where these competing narratives will ultimately collide is the Iowa caucus on January 3.” As Iowa drew closer, we opined that if Clinton could win in Iowa, the race for the nomination would be over. But if Obama won, the race would be a toss-up.

Obama did win, of course, displaying once again his team’s organizational skills, a prowess that would eventually capture the nomination by doing lots of little things right.

Iowa led to the New Hampshire primary, whose outcome disappointed Obama and embarrassed the polling industry. Rasmussen Reports issued a release asking “What Happened to Polls in New Hampshire?”

The next amazing event of the political season took place less than three weeks later in South Carolina where Bill Clinton clumsily addressed the topic of race while attempting to diminish the impact of Obama’s expected victory in that state. Not only did Obama win big, but the Clinton campaign approach played a role in getting Senator Ted Kennedy and his niece, Caroline, to endorse the Illinois senator. That changed the dynamic, and the possibility of an Obama victory suddenly became easier to envision.

While "Super Duper Tuesday" in early February when 23 states and territories held their primaries ended largely in a draw, Obama was ready to keep going, but Clinton was not. Obama wrapped up a solid string of primary and caucus victories to take the lead in the race by the end of that month. Then the trench warfare phase of the campaign began, with both candidates capitalizing on support from their core constituencies. There were few surprises, but Obama built a modest but steady lead.

At the time, many speculated that the ongoing struggle between Obama and Clinton would help the Republicans in the long run. It didn’t work out that way. In fact, the competition with Clinton actually produced two huge advantages for Obama.

First, the Obama-Clinton show dramatically increased the number of Democrats in the country while depleting the number of Republicans. At the end of December, just before Iowa, just 36% of Americans said they were Democrats, a number that grew to 41% by the time Obama wrapped up the nomination. During the same time frame, the number of Republicans fell from 34% to under 32% (see partisan identification by month). In effect, the primary campaign provided the equivalent of a long-lasting convention bounce for the Democrats, one that never completely faded.

The second big advantage for Obama was the string of one-on-one debates with Clinton. His debating skill improved as time went on, and he used that experience well when facing off against John McCain in the fall. McCain never participated in any one-on-one debates on his path to the Republican nomination.

Yet while we can point to specific landmarks along the way, the path blazed by President-elect Obama was truly remarkable and continues to defy easy explanation. It was made possible partly because the Clinton team was overconfident and not as disciplined as they should have been. Obama had the right theme as the agent of change while Clinton ran inexplicably as the candidate with experience. Obama’s organization was far more skilled and disciplined than Clinton's or McCain's.

But ultimately the explanation for Obama's victory comes down to the candidate himself. Obama brought powerful political instincts and skills to the campaign. He was able to inspire people in a way few politicians have in modern times. And he was the right person in the right place at the right time.