A new poll in Taiwan shows President Ma Ying-jeou is increasing his lead over opposition candidate Tsai Ing-wen ahead of elections scheduled for mid-January.

The poll released late Sunday showed Mr. Ma with a 7.3-percentage-point lead over Ms. Tsai in a head-to-head race, up from just 1.7 points a month ago. If third-party candidate James Soong enters the race, Mr. Ma's lead slips to 3.8 percentage points, compared to 0.7 points a month ago.

Mr. Ma's presidency has been marked by a series of trade and economic agreements with China aimed at boosting the island's economy while easing decades of tension with Beijing. Ms. Tsai is chairman of the independence-minded Democratic Progressive Party, though she says she would not reverse Mr. Ma's China-friendly policies.

China-Taiwan relations hit a low point under Taiwan's previous DPP government, led by President Chen Shui-bian.

The latest poll was conducted by the Taiwanese Association for Pacific Ocean Development, which is chaired by a former DPP official.