Bernie Sanders has rebuffed all questions about whether he will try an independent run at the White House, but that stance may be softening as the Vermont senator now appears open to the idea of bucking the Democratic Party and going it alone in his bid to win in November.

Sanders has been steadfast in his stance that keeping Donald Trump out of the White House is his top goal, and had used that justification against the possibility of a third-party run this fall. Sanders said he would refuse to play the spoiler, potentially splitting the left-leaning vote and allowing Trump to win.

But with the rapidly changing circumstances regarding the race, Bernie Sanders may now be considering an independent run. Sanders has proven to be the only Democratic candidate who can consistently beat Donald Trump in polls, a point he has pressed to the party’s superdelegates in a bid to win their support over Hillary Clinton and take the nomination. Clinton also remains embroiled in an FBI investigation that could potentially up-end her campaign, a point Sanders has not brought up publicly much but that could be in the back of the mind for superdelegates.

The strategy hasn’t brought results so far, as no superdelegates have yet to leave Clinton and support him, and there are signs that Bernie Sanders may be reconsidering an independent run. In an interview with KABC-TV 7 News, Sanders was asked about the offer from Green Party candidate Jill Stein for Sanders to fill the party’s ticket.

His answer was far from a definitive “no.”

“Right now, our goal is to win the Democratic nomination,” Sanders said.

Salon writers Kevin Zeese and Patrick Walker wrote that Bernie Sanders would be smart to consider an independent run, especially given his greater odds of defeating Donald Trump.

“Sanders leaving the door open to a Sanders-Stein ticket comes at a time when polls show unprecedented support for a candidate to challenge Donald Trump and Hillary Clinton. This week NBC found that 47% of voters would consider a third-party candidate if Clinton and Trump were the major-party nominees. In the last week, two other polls found a large minority will vote for a third party this year. Schoen Consulting found 20% of voters would vote for a third party against Clinton and Trump with 14% undecided; Data Targeting Inc. found 21% would do so with 14% undecided.”

The idea of an independent run has excited many supporters of Bernie Sanders, especially the “Bernie or Bust” contingent who have vowed not to support the Democratic Party if Clinton wins the nomination.

Bernie Sanders would win the White House even if he ran as an independent. #CaliforniasVoteMatters #FeelTheBern pic.twitter.com/4q2DJBQaIW — Eduardo Samaniego (@EduarSamani) June 5, 2016

At the same time that Bernie Sanders appears to be leaving the door open a crack for an independent run, he has also shown very public disdain with his treatment by the Democratic National Committee. Sanders has called out party chair Debbie Wasserman Schultz for her apparent favoritism toward Hillary Clinton and a process that was more often worked against him.

This weekend, the campaign called out the Puerto Rico Democratic Party for failing to approve poll workers to help inmates vote. That led to a sharp rebuke from party officials.

“Inmate voting is handled not by the Democratic Party but by the Commonwealth’s Absentee and Advance Vote Administrative Board,” Democratic Party President Roberto Prats said (via the Hill). “I have been told that the Sanders campaign submitted their prison pollworker list at 6:10 pm on the evening prior to inmate voting and began complaining early in the following morning that the Board had not completed their pollworker’s certification. But in the end, despite the late submittal, the Sanders campaign had representatives at the prison voting places.”

Sanders has shown frustration with apparent media collusion with the party, saying they would be wrong to declare Hillary Clinton the presumptive nominee on Tuesday when he still has a chance to win over superdelegates and secure the nomination.

“Now, I have heard reports that Secretary Clinton has said it’s all going to be over on Tuesday night. I have heard reports that the media, after the New Jersey results come in, are going to declare that it is all over. That simply is not accurate,” Sanders said (via the Washington Post).

If Bernie Sanders were to consider an independent bid for the White House, it may be too late for a full-fledged run. So-called “sore loser” laws would restrict or prevent him from getting on the ballot in a handful of states, meaning an all-out bid to win the Democratic nomination will still be his best bet of winning in November.

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