A fascinating experiment in technology-enabled participatory democracy is happening, right now, in Argentina.
They are called the Partido de 
la Red, and the Argentina Independent did a quality, thoughtful interview (in English) with their founders.
The basic idea is as follows: (1) Get members elected to government positions (2) All members can debate and vote on all issues via the online platform, and (3) The elected reps pledge to vote in accordance with the results of the public online vote.
The PdlR is more than mere concept: they won over 1% of the popular vote in the recent Buenos Aires City Legislative Elections. They have started work on their participatory internet platform (DemocracyOS) and will soon launch a kickstarter to fund continued development.
The group is, in many ways, reminiscent of an idea for a novel that I first wrote in the 90s and have been revising ever since. More on that, here, one of these days. Check out the article, below. 