The results marked an increase of six constituencies for the KMT, including in Taipei county, Ilan county and Chiayi city -- three constituencies traditionally held by the ruling Democratic Progressive Party (DPP).

The DPP only won six constituencies, down from its current nine. The other three seats were won by the People First Party, the New Party and an independent candidate, according to the commission.

"This is a victory for the people, for the democratic development in Taiwan," KMT chairman Ma Ying-jeou told cheering supporters at party headquarters in downtown Taipei, the island's capital.

At stake were mayoral seats in five cities and magistrate posts in 18 counties. Elections were not held in the capital and Taiwan's second largest city of Kaohsiung.

The KMT won 50.95 percent of the ballots cast while the DPP obtained 41.96 percent after vote counts at 12,081 polling stations were completed, the commission said