On Tuesday, Bernie Sanders finally formally endorsed Hillary Clinton at a rally in Portsmouth, New Hampshire. Sanders, who had challenged the conventional wisdom that Clinton was the de facto nominee of the Democratic Party by running a hard-left socialist campaign, told the crowd, "I have come here to make it as clear as possible why I am endorsing Hillary Clinton and why she must become our next president. Secretary Clinton has won the Democratic nomination and I congratulate her for that … I intend to do everything I can to make certain she will be the next president of the United States.” He added, “This campaign is not really about Hillary Clinton or Donald Trump or Bernie Sanders. This campaign is about the needs of the American people and addressing the very serious crises that we face. And there is no doubt in my mind that as we head into November, Hillary Clinton is far and away the best candidate to do that."

Yet Sanders could not resist bragging about himself before he ever mentioned Clinton, saying, "Let me begin by thanking the 13 million Americans who voted for me during the Democratic primaries. Our campaign won the primaries and caucuses in 22 states, and when the roll call at the Democratic National Convention is announced, it will show that we won almost 1,900 delegates."

Sanders admitted, "It is no secret that Hillary Clinton and I disagree on a number of issues, that is what this campaign has been about. This is what democracy is about." Then he boasted, "There was a significant coming together between the two campaigns and we produced by far the most progressive platform in the history of the Democratic Party.”

Sanders tweeted Tuesday morning:

While Clinton looked on, Sanders never acknowledged her presence, although he mentioned her name quite often. As CNN reported, “After concluding his speech, Sanders appeared to move in for a handshake -- which Clinton ignored by stretching out her arms and offering a hug, instead.”

Clinton rejoiced, "We are joining forces to defeat Donald Trump! I can't help but say how much more enjoyable this election is going to be when we are on the same side. You know what? We are stronger together!"

Appealing to Sanders’ supporters, Clinton trumpeted that she had moved to the left on many issues, including minimum wage; the Trans-Pacific Partnership trade deal, and making college affordable for students with a new college affordability plan that proposes tuition-free enrollment in public in-state colleges for families earning up to $85,000.

Clinton placated Sanders’ supporters by adding, "Sen. Sanders has brought people off the sidelines and into the political process. He has energized and inspired a generation of young people who care deeply about our country. To everyone here and everyone cross the country who poured your heart and soul into Sen. Sanders' campaign: Thank you."

Robby Mook, Clinton's campaign manager, and Jeff Weaver, Sanders' top aide, had been negotiating how Sanders would endorse Clinton for weeks. CNN reported that Mook has met with Sanders' delegates in New Hampshire and Vermont. Marlon Marshall, Clinton’s director of States and Political Engagement, spoke with Sanders delegates in Wyoming. Jake Sullivan, Clinton's top policy adviser, spoke with Sanders supporters in the state of Washington.

Barney Frank, who co-chairs the Democratic Party's Rules Committee, enthused that Sanders’ endorsement will help Clinton "enormously,” but acknowledged that Clinton may face a difficult task ingratiating herself with Sanders’ supporters, He said, "Given, frankly, some of the criticism that he made, I think it will take work to get all of them there.”

Donald Trump tried to appeal to Sanders’ supporters himself, tweeting, "I am somewhat surprised that Bernie Sanders was not true to himself and his supporters. They are not happy that he is selling out!"