In a related story,

Incarcerated former president Chen Shui-bian has thrown his weight behind Tsai Ing-wen's presidential bid, listing a total of 10 reasons for his supporting the current DPP chairperson in an open letter,

which was shown to the media yesterday by his son, Kaohsiung city councilor Chen Chih-chung. The younger Chen said that his father credits Tsai for leading the DPP out of its worst crisis after the 2008 election defeat, and considers her the most qualified challenger to President Ma in 2012.

Chen made no direct mention of the

other DPP contender, Su Tseng-chang, in the letter.

And it's not yet clear at this point how much influence Chen's opinions will have on the results of the opposition party's primary.