  In recent years, political parties have adopted Online Delegative Democracy
platforms such as LiquidFeedback to organise themselves and their political
agendas via a grassroots approach. A common objection against the use of these
platforms is the delegation system, where a user can delegate his vote to
another user, giving rise to so-called super-voters, i.e. powerful users who
receive many delegations. It has been asserted in the past that the presence of
these super-voters undermines the democratic process, and therefore delegative
democracy should be avoided. In this paper, we look at the emergence of
super-voters in the largest delegative online democracy platform worldwide,
operated by Germany's Pirate Party. We investigate the distribution of power
within the party systematically, study whether super-voters exist, and explore
the influence they have on the outcome of votings conducted online. While we
find that the theoretical power of super-voters is indeed high, we also observe
that they use their power wisely. Super-voters do not fully act on their power
to change the outcome of votes, but they vote in favour of proposals with the
majority of voters in many cases thereby exhibiting a stabilising effect on the
system. We use these findings to present a novel class of power indices that
considers observed voting biases and gives significantly better predictions
than state-of-the-art measures.
