In an interview with C-SPAN, Democratic presidential candidate Bernie Sanders said in the strongest terms yet that he will not be the Democratic nominee for president. (C-SPAN)

In an interview with C-SPAN, Democratic presidential candidate Bernie Sanders said in the strongest terms yet that he will not be the Democratic nominee for president. (C-SPAN)

A few hours before making his third appearance at New York’s Town Hall on Thursday afternoon, Bernie Sanders taped his fifth appearance on “The Late Show With Stephen Colbert.” Previously, Colbert had treated his guest as a scrappy underdog. This time, Colbert asked whether Sanders was ever going to stop running for president.

“Is there anything you’re going to announce in the speech that you may want help phrasing?” Colbert said. “Do you want to be ambassador to Narnia?”

The senator from Vermont laid out in his speech the next steps of his campaign for “social justice” and political reform. On Friday, he’ll deliver a similar one in Albany, then stump with a congressional candidate in Syracuse. In St. Louis, five of his closest allies will try to add progressive planks to the Democratic platform.

“Election days come and go, but what is much more important is that political and social revolutions continue,” h said in his speech. “Our goal from day one has been to transform this nation, and that is the fight we are going to continue.”

Sanders, who has no plans to endorse or appear with Hillary Clinton ahead of the Democratic National Convention, is in the midst of his own transition. Once a quietly influential senator, he has rejoined that body as a political icon, trailed (for the time being) by a retinue of Secret Service agents. At state conventions and the platform-drafting meetings, he is winning concessions on the issues he once talked about to an invisible C-SPAN audience.

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“We’ve been talking and brainstorming how we can take the momentum of this campaign and weave it into the DNA of the convention,” said Sen. Jeff Merkley (D-Ore.), Sander’s lone Senate endorser, who sat with the candidate during his Monday afternoon return to the Capitol. “He field-tested these ideas, and they resonated beyond anything that the caucus anticipated. Every person in the caucus has said: Look, look at how much people care about this.”

But not since 1992, when once and future California Gov. Jerry Brown ran a less-successful populist campaign for the presidency, has a defeated candidate kept his campaign going until the convention. Sanders has watched allies such as Merkley acknowledge that Clinton will be the party’s nominee. He has quietly abandoned an effort to convince superdelegates to switch to his campaign.

Meanwhile, her campaign’s delegate advantage and knowledge of party rules has allowed her to consolidate control. Last week, the Democratic National Committee devolved some responsibilities from Chairwoman Debbie Wasserman Schultz (who Sanders wants to remove) and handed them to Brandon Davis, a Clinton ally and the national political coordinator for the Service Employees International Union. On Tuesday, Clinton allies were seated as delegates from the District, winning roles that local politicians had coveted.

Three members of the D.C. Democratic State Committee said the surprise orders regarding which delegates to seat came from the Clinton campaign all at once Monday evening. Party officials were in the office of D.C. Democratic Party Chairwoman Anita Bonds, preparing for Tuesday’s vote on the seats when a barrage of phone calls, emails and text messages came in from the campaign and the DNC. “It was the night of the long knives,” said one longtime state committee member who was present at the meeting.

Two days earlier, in what had almost become a courtesy, Bonds had sent the Clinton campaign a list of 52 names of people vying for five at-large seats and two set aside for elected leaders. No presumptive Democratic nominee for president had interfered with the election of those local delegates in at least three decades, according to the party’s general counsel.

Instead, Bonds said she received an email from the campaign regarding the 52 names: All had been scratched except seven approved by the campaign — and none were elected officials, or even well known to many local Democrats. Steve Elmendorf, a Democratic lobbyist who won one of the seats, said he had not heard of any discord until The Washington Post asked him about it.

Bonds had the duty of delivering the news to the committee.

Democratic presidential candidate Bernie Sanders arrives to speak at a rally in Manhattan Thursday. (Lucas Jackson/Reuters)

“People were like, ‘Who are these people? What is this?’ They were upset,” Bonds said.

Party chairs in dozens of states have been given similar marching orders, Bonds said. She called it a prudent move for the Democratic convention to succeed at a time when Republicans seem to be floundering.

“I think it’s her covering her flank,” Bonds said. “You want people who have worked with you, worked with your campaign, who have shown commitment to help you protect the party, and that’s what many of these individuals will do.”

Not everyone was as forgiving. Franklin Garcia, the city’s “shadow” representative to Congress and who was lobbying for one of the delegate seats, said the interference by the campaign was disappointing. Even though four local delegates are Latino, Garcia said imposing the names cut out an important voice for the District’s Latinos.

“Truth is, even though the delegation has some Latinos by name, none of them have a base in the community,” he said. “We cheated our community of representation in this process.”

The platform drafting committee has proven to be less fractious. Negotiations between the Clinton and Sanders campaigns began in earnest after Clinton claimed victory on June 7, two Democrats familiar with the process said. The goal of talks, mostly conducted by phone by proxies for the candidates, have narrowed the areas of disagreement over policies including the minimum wage and U.S. policy in the Middle East, Democrats said.

That probably will mean that a consensus platform document will emerge from a two-day meeting of the platform drafting committee Friday and Saturday, Democrats close to each campaign said. A Clinton ally downplayed the chance of a showdown over the Democratic Party platform ahead of the nominating convention, and Sanders himself seemed to telegraph significant agreement in an opinion piece published Thursday in The Post.

The Sanders essay, titled “Here’s What We Want” listed mostly issues on which he and Clinton agree, including overturning the Supreme Court’s Citizens United campaign finance decision, universal voter registration, clean energy investment and a reduction in the U.S. prison population.

He also listed his call for a ban on fracking, which Clinton does not support, and his call for universal health-care coverage, which she shares by a different route than Sanders supports. He did not mention his proposal for free college tuition, which she vigorously opposes, or a universal $15 minimum wage, which she considers too inflexible, or U.S. policy toward Israel and the Palestinians.

The goal of secret discussions in the past week was to work out compromises on those differences that would avert a floor fight at the Philadelphia convention, Democrats said.

“It is possible to write language that gets at the goal of affordable college, for instance, or a higher minimum wage,” one Democrat familiar with the process said.

The question of what emphasis to put on Palestinian rights could also be finessed, Democrats said, even though some Sanders and Clinton backers see the issue very differently.

Those differences were visible in the Senate, as well. Since returning, Sanders has taken up the opposition to a compromise that would tackle Puerto Rico’s debt crisis by handing control, temporarily, to a Republican-dominated emergency board. On Thursday morning, speaking to Latino legislators who had gathered for a Washington conference, he warned them that Congress would exploit the crisis and cut wages for very poor people if no one acted.

“Vulture funds have been buying up funds for pennies at the dollar,” he said. “What they now want to do is get 100 percent of what the bonds are worth at very, very high interest rates. I believe it is immoral to give Wall Street speculators large profits literally on the backs of the poor and small children.”

Sanders did not mention his own legislation, which would allow the Federal Reserve to buy up Puerto Rican debt, and which has attracted little support from fellow Democrats. He wrapped up and headed to New York.

Anne Gearan contributed to this report.