Nicole Gaudiano

USA TODAY

WASHINGTON — His presidential aspirations behind him, Bernie Sanders is looking ahead to a busy future in which he continues to focus on nothing less than transforming the Democratic Party and the country.

In an exclusive interview with USA TODAY, the Vermont senator detailed plans to launch educational and political organizations within the next few weeks to keep his progressive movement alive. The Sanders Institute will help raise awareness of "enormous crises” facing Americans. The Our Revolution political organization will help recruit, train and fund progressive candidates' campaigns. And a third political organization may play a more direct role in campaign advertising.

Sanders plans to support at least 100 candidates running for a wide range of public offices — from local school boards to Congress — at least through the 2016 elections. And he’ll continue to raise funds for candidates while campaigning for them all over the country. He said he probably will campaign for Tim Canova, a progressive primary challenger to Rep. Debbie Wasserman Schultz of Florida, who chairs the Democratic National Committee.

“If we are successful, what it will mean is that the progressive message and the issues that I campaigned on will be increasingly spread throughout this country,” Sanders said. “The goal here is to do what I think the Democratic establishment has not been very effective in doing. And that is at the grass-roots level, encourage people to get involved, give them the tools they need to win, help them financially.”

Speaking in his Senate office surrounded by pictures of Vermont, Sanders also addressed the fight he still plans to take to the Democratic National Convention that begins July 25 in Philadelphia.

After endorsing Hillary Clinton at a joint campaign event in Portsmouth, N.H., on Tuesday, Sanders said he'll do everything he can to defeat presumptive GOP nominee Donald Trump. And he plans to become active in Clinton’s campaign — probably in “some kind of joint efforts” and independently — after the convention later this month.

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But Sanders said he'll remain a candidate until Clinton’s official nomination so his nearly 1,900 delegates can cast their ballots for him at the convention.

“I want the country and the world and our people to appreciate the kind of success we’ve had,” he said.

As part of his goal to transform the Democratic Party, Sanders said, he'll continue to push for electoral reforms when the party’s rules committee meets before the convention.

"If we’re not successful there, we will take those issues to the floor,” he said.

He's calling for increased grass-roots activism, opening up primaries to independent voters, and reforming the rules that allowed many superdelegates — the party officials and leaders who are free to vote for the candidate of their choice at each convention — to endorse Clinton early in this year's process, before Sanders became a candidate.

“That’s not Democratic and that’s wrong and that’s got to change,” he said.

After Sanders endorsed Clinton, some of his supporters took to social media to vent their frustration and disappointment. Sanders said he felt disappointed as well. But he noted that the progressive movement isn’t strong in this country and said it's significant that many of his ideas have been incorporated into the Democratic Party platform. The best path forward, he said, is not to “sulk” or “argue with each other."

“The way to go forward is to build a progressive movement around a very progressive agenda,” he said. “What you’re seeing is more traditional Democrats, more establishment Democrats, move in our direction because they see the support out there for our ideas.”

Sanders also is writing a book titled, Our Revolution: A Future to Believe In, his publisher announced Thursday. But he declined to discuss that in his signature blunt style.

“Stay on the issue, let’s go,” he said at the beginning of the interview. “Let’s start with the real stuff.”

Nearly 24,000 people have signed up on Sanders' website for information about running for office or helping people run for office in response to a June 16 video address in which Sanders urged his supporters to take action. At subsequent events, Sanders met privately with groups of those people, talking with them in “professorial mode” about why he originally ran for office, said Shannon Jackson, who will head Our Revolution.

Jackson recalled that one woman at an event in Syracuse, N.Y. said she wanted to run for local office and another woman wanted to volunteer. Sanders told the second woman, "Well, you can be her campaign manager,” Jackson recalled. “And he married them up in the room. I think there’s going to be a lot more opportunities to show people that it’s not hard to run for office, you can do this, you can start at the bottom and go up. That’s what the senator did.”

Sanders said Democrats' loss of about 900 state legislative seats in nearly eight years tells him a strong grass-roots movement is needed to get people to run for office and to show them how — from getting on the ballot to running TV ads. Our Revolution, a 501(c)(4) political organization, will work with several progressive groups to train and vet candidates.

Sanders said he wants to make sure candidates receiving such help are, in fact, progressive. But they don’t have to be Democrats.

“If you have some strong independents who would like to run, it would be my inclination to support them,” he said.

He especially wants young people and working people — two of his key constituencies — to feel comfortable about getting more involved in the political process. As a progressive agenda becomes more accepted by the mainstream, he said, more elected officials will be prepared to take on big-money interests and other issues he addressed in his campaign.

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Following his re-election in 2012, President Obama launched Organizing for Action as the political successor organization pushing his agenda. Sanders said he doesn’t plan to “reinvent the wheel,” but his effort is unique in that it will build off his campaign and the millions of names in its database. He plans to maintain control of his email list

The Sanders Institute will focus on elevating issues and ideas — through media and documentaries — that Sanders said the “corporate media” fails to focus on, including the disappearing middle class, “massive” income inequality, horrific levels of poverty and problems affecting seniors and children.

Jane Sanders, Sanders’ wife and political adviser, said the organization will help address issues that came into sharp focus on the campaign trail, such as “heartbreaking” issues facing Native Americans, and possible solutions the campaign discovered to address their health care needs.

“It would be ridiculous for us to learn and not convey that information,” she said.

Sanders repeated his mantra that big-money interests won't be "dislodged" unless millions of people get involved in the political process.

“The campaign is coming to an end,” he said. “But to my mind, what is absolutely imperative is that we keep the movement alive.”