If Bernie seeks the Democratic nomination, it doesn't MATTER what his voter registration is.

[MADem]

169. I'm not from VT, so I can't speak to state or local elections.

I do understand that VOTERS don't declare a party affiliation. I don't know if the state election officials require candidates to self-identify. I know in local elections in MA, it's not required, but state candidates do identify themselves by party affiliation.

However, candidates for FEDERAL offices (Senate/Representative/POTUS/VPOTUS) have to file a candidacy declaration with the Federal Election Commission BEFORE any election takes place (no matter what state they are from), within fifteen days of their ANNOUNCEMENT that they are running for office--so that would be well before any ballots are even printed. On that form they are required to tell the FEC what their party affiliation is, and who is collecting the money for their campaign. That MONEY piece is a good part of what they're interested in!

Here are some of the FEC filings.

Patrick Leahy (Democratic Party): http://www.fec.gov/fecviewer/CandidateCommitteeDetail.do?&tabIndex=3&electionYr=2016&candidateCommitteeId=S4VT00017

Bernie Sanders (Independent): http://www.fec.gov/fecviewer/CandidateCommitteeDetail.do?&tabIndex=1&candidateCommitteeId=S4VT00033


Here's a "matching funds" report where a grouping of candidates are identified by their party affiliation:

http://www.fec.gov/press/20031230certification.html

And here's a list of everyone (nearly 300 people!!!!) who have filed a form 2 so far with the FEC to run for President in 2016:

http://www.fec.gov/press/resources/2016presidential_form2nm.shtml

They haven't received Sanders' form yet, but he's got two weeks to get it in. And of course, not all of those people will be on the ballot. It's a long road between declaring candidacy and actually getting on even a primary ballot, never mind the general election one!