It is impossible to talk about the LDP today without acknowledging that the party — and thus Japan’s political system — stands in the shadow of Koizumi Junichiro.

For his enemies in the party, branded by Mr. Koizumi as “opposition forces,” he is the symbol of everything they loathe, enabler of what the French call “Anglo-Saxon” market fundamentalism. To the Japanese people and his followers within the LDP, he is the symbol for the changes Japan needs to make in order to remain successful, and a decisive break from the old way of politics. Despite withdrawing from the spotlight since leaving the premiership in September 2006, he is the man central to any discussion about Japan’s political future, even if the man himself is likely to remain on the sidelines (and may even be out of the Diet by the next House of Representatives election).

Not surprisingly, then, both Mr. Fukuda and Mr. Aso are positioning themselves in relation to Mr. K. Mr. Fukuda, whatever his personal disputes with Mr. Koizumi, has positioned himself firmly in the Koizumi stream, with the caveat that “If problems arise, reform should be carefully amended.” Mr. Aso, however, has been described as taking on a distinctly “leaving Koizumi behind” cast. Consistent with his “rural insurgency” campaign strategy, he is using phrases like “market fundamentalism” to argue for prioritizing the concerns of rural Japan over pushing ahead with painful reforms.

For the LDP’s short-term political prospects, it cannot be an either/or decision. By dint of his charisma, Mr. Koizumi was able to forge a national movement under the LDP umbrella that could compete in the cities without chasing rural Japanese from the LDP. Absent that charisma? The increasing incompatible and contradictory interests of urban and rural Japan have become apparent. As Takenaka Heizo, Mr. Koizumi’s former lieutenant, writes in Sankei, the legacy of Mr. Koizumi is as much about appearances as about substance: “In a democratic society, to make policy for the people, the government has the responsibility both to explain policy in a way that is easily understood by the people and to execute.” For Mr. Takenaka, Mr. Abe’s problem is that he failed to market his policies well, and poor personnel selections hindered his ability to execute.

And so the LDP’s dilemma. One candidate says the right things and will undoubtedly be wise in his choice of advisers but is utterly lacking in charisma; the other desires a departure from Mr. Koizumi’s path, but has popular appeal and the ability to attract voters to his side throughout the country, including younger voters in cities. For the time being, it seems like Mr. Fukuda will do, but it is unclear to me whether he will be able to reassemble the Koizumi movement that led the LDP to a historic victory in 2005. Is there a leader in the LDP who can? I’m skeptical, and so I wonder how much longer the LDP can last as a party that it is trying to compete in the cities without losing its rural supporters (or vice versa). The DPJ obviously faces similar pressures, but the LDP, as the ruling party, has more at stake.