Now is a critical time for the Liberal Democratic Party (LDP). Taro Aso, the newly elected party president, needs to get serious and face up to important issues in a speedy and bold manner.

Aso scored an overwhelming victory in Monday's party leadership election to become the 23rd LDP president, defeating four other candidates – Kaoru Yosano, state minister in charge of economic and fiscal policy; Yuriko Koike, former defense minister; Nobuteru Ishihara, former chairman of the LDP Policy Research Council; and Shigeru Ishiba, former defense minister.

Aso is set to be named prime minister at an extraordinary Diet session that convenes today.

Aso's grandfather is Shigeru Yoshida, who served as prime minister for a number of years just after World War II.

The prime minister's post has most recently been held by scions of political dynasties, Yasuo Fukuda and Shinzo Abe, both of whom abruptly resigned. Aso needs to demonstrate his strong sense of responsibility and staying power.

Why did Aso defeat the other four candidates by such a big margin?

This was the fourth time for Aso to run for party president. Having his own small faction as a stronghold, Aso gained support from members of all of the party's factions as he went through three campaigns for the party's top post since 2006.

His upbeat and unique character attracted popular support. In recent opinion polls, Aso was ranked as the person most suitable for the prime minister's post.

Party members are pinning their hopes on Aso as the face of the party with the dissolution of the House of Representatives and a general election expected soon.

Unlike Fukuda, who lacked the ability to convey strong messages, Aso was evaluated highly for his communication skills.

Many LDP Diet members and local chapter representatives decided to support Aso in the hopes of being on the winning side. As the cases of Abe and Fukuda showed, however, an overwhelming victory in a party race does not necessarily mean the winner can expect stable support from party members.

In appointing four main party executives, Aso retained incumbents in three of the four posts. For the post of party secretary-general that he previously occupied, Aso picked Hiroyuki Hosoda, acting secretary-general of the party. By retaining the previous executive lineup, Aso appears to be trying to ensure a smooth transition.

Having elected Aso as party president, LDP lawmakers have a responsibility to support the new leader by building party unity.

The relationship with the LDP's junior coalition partner New Komeito is also important. The ruling parties' relationship soured in the final days of the Fukuda administration over such issues as a bill to revise the new Anti-Terrorism Law to allow the Maritime Self-Defense Force to continue its refueling mission in the Indian Ocean and envisaged fixed-sum tax breaks.

It is necessary to strengthen the relationship with New Komeito to foster cooperation in the next lower house election. Reconfirming the two parties' ties is an urgent task for Aso.