WASHINGTON -- Pennsylvania Democratic leaders, aided by a surprise pitch from Sen. Cory Booker (D., N.J.), appealed to Bernie Sanders supporters to unite behind Hillary Clinton Monday morning as the Democratic National Convention kicked off -- but were met with firm resistance.

"We want you, we need you, we want you to be part of us," said Marcel Groen, chairman of the Pennsylvania Democratic party. Opening the Pennsylvania delegation's first breakfast, he asked Sanders delegates to stand. As they did -- some holding their fists in the air -- the room applauded.

"We need your thoughts, we need your ideas, we need your passion," Groen said.

But the passion for Sanders has not cooled for many, interviews with Sanders supporters in the room showed.

" I honestly don't care about party unity -- I care about people unity," said Amanda McIllmurray, a 23-year-old Philadelphian. "If a party doesn't support us and doesn't pass policies that are beneficial for the general public, then I don't really care to support them."

She waved off concerns that failing to support Clinton could lead to a Donald Trump presidency, saying the Democratic National Committee, which she believes aided Clinton in the primary,  put "people in this situation to vote for somebody who really doesn't reflect the majority of Americans' values and is viewed as untrustworthy."

At almost the same time, Sanders supporters at a Florida delegation breakfast were booing off the stage the chairwoman of the national committee, Debbie Wasserman Schultz. At a rally later in the day, more boos erupted when Sanders called for electing Clinton.

McIllmurray was one of four Sanders supporters interviewed at the Pennsylvania breakfast. Each expressed reservations about Clinton, and downplayed talk that they should fall in line to defeat Trump.

"I personally am not convinced that if she were elected, that Hillary Clinton would use her power in the White House to make progress for working people," said Arianna Flores Gordon, who, along with a friend, wore a homemade paper tiara cut out to read "Bernie."

"I personally believe that everyone should vote according to their conscience and not vote for someone out of fear that if they don't, another person will win," said Flores Gordon, 32, of Philadelphia.

Another Sanders delegate, Steve Todd, said his mind isn't made up, and that Clinton is "moving in the right direction," but that when he thinks about what to do on Election Day, "I'm struggling with it as a person ... We are in a battle for the very soul of our nation and we have to be comfortable that Hillary will be a liberal representative."

Democrats hope that when Sanders addresses the crowd tonight, he can bring his supporters onto Clinton's side in an effort to beat Trump. Booker also has a prime time slot, along with Sen. Elizabeth Warren, another champion on the left who is backing Clinton, and first lady Michelle Obama. Locally, Sen. Bob Casey, Mayor Kenney and U.S. Reps. Bob Brady and Brendan Boyle, both of Philadelphia, will also address the convention.

At the Pennsylvania breakfast, Booker urged Democrats to "come in with our energy and our light and our love" to counter "the bile ... vitriol" and "hate that was spewed in that Republican convention," last week.

(Asked if he was disappointed about being passed over for the vice presidential slot, he said with a smile, "I'm just excited that I was in the conversation.")

While insurgents still support Sanders, the Democratic party establishment is comfortable with Clinton -- and party leaders believe she can eventually win over Sanders loyalists.

"The Bernie people have nothing in common with Donald Trump," said U.S. Rep. Mike Doyle, of the Pittsburgh area. "If the election were today, they'd vote for Hillary."

Clinton's camp also pointed to other Sanders supporters who are now supporting Clinton, including Lou Agre, a ward leader from Roxborough.

"I have to support Hillary Clinton because of where I live - and where I live is in the real world," said Agre, a business representative for a local chapter of the operating engineers' union. He said a Trump presidency would be a disaster for climate change and other issues. "In the long run, I think the large, large majority (of Sanders supporters) will end up voting for Hillary Clinton."

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