How has Bernie actually been doing vote-wise, if the system were to look like the GOP one?
Well, they supposedly split 50/50 in Iowa but there are many accusations of vote fraud there favorable to Hillary that the democrat party won't release the vote totals.
See this:
http://townhall.com/tipsheet/christinerousselle/2016/02/09/awkward-iowa-dems-are-refusing-to-release-raw-vote-totals-n2117005
In New Hampshire Bernie won 60% to Hillary's 38%
Vote count: Bernie = 151,584
Hillary = 95,252
Source: http://www.wmur.com/politics/2016-full-new-hampshire-presidential-primary-election-results/37649066