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BEIJING -- The world's two biggest economies choose their next leaders in early November, an accident of timing that lays bare the vivid contrast between China's opaque communist state and America's riotous democracy. 

The rhythm of the presidential election in the United States has been set by three televised debates watched by tens of millions of voters, with campaigning carried out online as well as at boisterous rallies that draw thousands.

On the other side of the Pacific the power games are under way behind closed doors, as Communist Party leaders jostle for positions ahead of the regime's once-in-a-decade leadership change starting on Nov. 8 at a special congress.

The victor of the Nov. 6 contest between Democratic President Barack...