In order to be on the ballot in the first-in-the-nation primary, candidates must be a registered member of either the Democrat or Republican party.
Sanders is an independent who caucuses with Democrats in the Senate, representing neighboring Vermont. When he filed for the New Hampshire primary earlier this month, he stated he was running as a Democrat and the state's secretary of state did not challenge his qualifications.
Andy Martin, who has filed himself as a Republican presidential candidate in New Hampshire, spoke at a hearing in front of the state's Ballot Law Commission via phone from San Francisco and argued that Sanders has no standing to run
in the first-in-the-nation primary as a Democrat.
"Mr. Sanders claims that he can run as a Democrat in New Hampshire 'because there is no party registration in Vermont.' The claim is a complete red herring," Martin wrote in a complaint.
Martin gained some fame during the Obama's first White House run for his claim that Obama was a Muslim. The New York Times reported in 2008
that Martin spread the rumor in a 2004 press release titled, "Obama is a Muslim who has concealed his religion."
Brad Cook, the chairman of the Ballot Law Commission, said Sanders' identification as an independent in the Senate did raise legitimate questions.
But during the hearing New Hampshire state Democratic Party Chairman Ray Buckley defended Sanders's place in the party and ultimately convinced members of the commission to keep Sanders on the ballot.
"You need a pretty convincing argument to deprive somebody of their place on the ballot," Cook told reporters after the vote.
Sanders' campaign said it had remained confident of the senator's qualifications throughout the process.
"We're pleased, but not surprised. Obviously, the senator has received great support from the Democratic Party and Democratic voters in this state. We came into this confident that this was not going to be an issue," Julia Barnes, the Sanders campaign's state director in New Hampshire, told reporters after the decision.
The commission also heard testimony challenging the eligibility of Donald Trump
based on party affiliation, but dismissed the complaint.
and Ted Cruz
were also challenged, but on a different basis. Complaints alleged that the two Republican candidates were ineligible to be on the ballot because they are not "natural born" citizens.
However, the commission decided the determination was not up to them.
"Our precedents say we don't go there," Cook told reporters of the Rubio and Cruz cases. "Personally, would I like the U.S. Supreme Court to decide these issues so we know what it is, so it doesn't keep coming up? Absolutely. Are we the vehicle to start that discussion? No, we're not. "