Tsai Ing-wen is set to win big in Taiwan's presidential elections on Saturday, defeating the incumbent party and possibly shifting how the island deals with the mainland.

Taiwan is heading to the polls on Saturday and Tsai Ing-wen, who has said she's ready to change the way the island has dealt with mainland China for about the past decade, is poised to become the next president.

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The relationship between Taiwan and mainland China can be described as "complicated," if you're feeling charitable. The short version: after the Communist takeover in 1949, the former regime fled to Taiwan, with both saying they represented all of China.

The relationship between Taiwan and mainland China can be described as

Over the years they've sunk into an uneasy truce, with China maintaining that Taiwan is a part of China but giving the island some autonomy as long as it doesn't declare independence. Both sides are heavily armed and there have been a few near-misses of war between the two since the 1950s.

For its part, the United States said in the 1972 Shanghai Communique establishing relations with the People's Republic of China that it "acknowledges that all Chinese on either side of the Taiwan Strait maintain there is but one China and that Taiwan is a part of China. The United States Government does not challenge that position."

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For the last eight years, Ma Ying-jeou, head of the Kuomintang (KMT or Nationalist) party founded by the leaders that originally fled the mainland, led Taiwain. Despite that history, Ma pushed for stronger ties with Beijing through his two terms.

For the last eight years, Ma Ying-jeou, head of the Kuomintang (KMT or Nationalist) party founded by the leaders that originally fled the mainland, led Taiwain. Despite that history, Ma pushed for stronger ties with Beijing through his two terms.