(CN) — Vermont Sen. Bernie Sanders will make his first joint appearance with one-time rival Hillary Clinton on Tuesday at a New Hampshire event at which he will formally endorse her for president, the Clinton campaign says.
The event is scheduled to be held at a high school in Portsmouth, New Hampshire.
Sanders soundly defeated Clinton in the New Hampshire primary on February 9, garnering 60.4 percent of the vote to her 38 percent.
Sanders' endorsement will come a month after the final primary and after protracted negotiations over the Democratic party platform.
Over the weekend, the senator's campaign released a flurry of emails trumpeting Sander's ability to get the part to adopt the "most progressive platform in party history."
Sanders pushed for policy agreements on higher education, health care, immigration reform, and a $15 an hour federal minimum wage.
"We have made enormous strides," Sanders said Sunday, but also said "the fight is just beginning."
"If we are going to transform America and create a government which works for all and not just the 1 percent we need to elect candidates who will fight for these principles," he said. "We need to elect a Democratic Congress and president and make certain that the language in the Democratic platform is translated into law."
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