Sen. Bernard Sanders received a big boost to his campaign Thursday with the endorsements of Communications Workers of America and Democracy for America and emphasized the grassroots nature of the endorsements.  

At a news conference with Sanders, Chris Shelton, president of the CWA, emphasized that the decision came directly from union members themselves after the union asked if it should endorse in the election, and if so, who should it endorse.  

“I am very proud of the fact CWA went with members,” Shelton said. “I think that’s the way it should be I think an endorsement coming from me would be an empty endorsement.”  

Sanders thanked the union for the endorsement, saying he knew it was not just a “press release endorsement.”  

“We are going to have thousands of people on the ground,” Sanders said. So far, many major labor unions have backed Hillary Clinton, including the National Education Association, the American Federation of Teachers and the Service Employees International Union. Sanders meanwhile has received backing from National Nurses United and the American Postal Workers’ Union.  

“What we are seeing is a lot of grassroots support in union after union throughout this country but that support has not trickled up,” Sanders said.  

Sanders also Thursday received the support of Democracy for America, a progressive organization founded by presidential candidate Howard Dean. Charles Chamberlain, executive director for Democracy for America, said on a conference call that Sanders had received 87.9 percent of more than 271,000 votes cast by members of the organization.  

The organization was one of many that tried to encourage Sen. Elizabeth Warren to run for president.  

“There is a huge amount of energy for populist progressive ideas,” Chamberlain said, speaking about what he called the “Warren wing” of the party. “That’s something they absolutely align 100 percent on the Bernie Sanders campaign.”  

Jeff Weaver, Sanders’ campaign manager, joined the conference call and spoke about the grassroots nature of both CWA and Democracy for America’s endorsements.  

“These are endorsements that were conducted after a vote by the members organization,” Weaver said. “When you go to the grassroots and ask people who they want to be the next president, people are pretty clear they want Bernie Sanders.”  

Both the CWA and Democracy for America said they would use their resources, including money, to help Sanders’ candidacy, despite Sanders criticism of super PACs in politics.  

“If Bernie doesn’t want to take it, OK I respect that,” Shelton said, while Democracy for America said it would be working with Sanders’ campaign to find the best way to help.  

America Rising, a conservative political action committee, noted that the CWA did not endorse Clinton or then-Sen. Barack Obama.  

“Maybe if Clinton hadn’t built a career on saying or doing whatever was most politically popular she’d have had a chance,” a press release said.

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