TAIPEI, Taiwan (AP) — Taiwan's relations with historic foe China are playing a key role in local elections on the self-ruled island Saturday as the ruling Nationalist Party meets increased resistance to forging stronger ties with Beijing.

Voters on the island with a population of about 23 million will elect representatives to 11,130 local seats, including mayoral posts in major cities such as the capital, Taipei.

A poor showing for the Nationalists would make it easier for the rival Democratic Progressive Party to win the presidency in early 2016, an outcome expected to disrupt negotiations with China on trade and investment deals that have lifted Taiwan's half-trillion-dollar economy while raising Beijing's hopes for political reunification.

Beijing has claimed sovereignty over Taiwan since the Chinese civil war of the 1940s, keeping relations icy until Nationalist President Ma Ying-jeou took office in 2008. He set aside the sovereignty issue to ease tensions and bind Taiwan to China's massive economy.

The Democratic Progressive Party questions deals with China as long as the Communist leadership wants to reunify with a reluctant Taiwan. Their cause received support in March when thousands of student-led protesters known as the Sunflower Movement occupied parliament and nearby streets in Taipei to stop ratification of a service trade liberalization agreement.

"Taiwanese haven't gotten the advantages they expected from relations with China, and those who have are a minority," said Ku Chung-hwa, a retired sociology professor who planned to vote Saturday. "The Sunflower Movement's influence is huge. It represents a whole generation."

When Democratic Progressive Party President Chen Shui-bian held office from 2000 to 2008, he angered China by advocating constitutional independence for Taiwan. Beijing threatened then to use force if needed.

The party has eased its stance since then but remains more cautious about relations with China than the Nationalists.

Alan Romberg, East Asia Program director with the Stimson Institute, a think tank in Washington, said the opposition party remained a wild card in Taiwan-China relations.

"The Democratic Progressive Party has made a number of adjustments over time, moving from outright opposition to various economic ties to acceptance of such ties as important," he said, adding it had nonetheless criticized the bilateral trade agreement pushed by Ma.