The Democratic National Convention in Philadelphia in July seems set to continue the fierce nomination battle — and launch a major debate about what the party stands for. Senator Bernie Sanders, independent of Vermont, won the Oregon primary handily on Tuesday and was barely edged out in Kentucky. Last week, he took West Virginia by almost 16 percentage points. Yet, supporters of former Secretary of State Hillary Clinton are already calling for him to stand down. The Clinton team is intent on putting on a tightly scripted convention show that displays unity behind Clinton and focuses the attack on presumptive Republican nominee Donald Trump. But an early exit by Sanders remains unlikely. He has defined his campaign as building a movement to transform the Democratic Party and change the direction of the nation. He has stated repeatedly that he will carry that argument into the convention. With many polls showing him beating Trump by greater margins than Clinton, Sanders can assert that pressing her to embrace more of his ideas will strengthen rather than weaken the former secretary of state in the general election. From the start of his campaign, Sanders has argued that the issues on his agenda go to the heart of what Democrats stand for. He wants the Democratic Party platform to include: support for a federal minimum wage of $15 an hour; the right to form unions; changes in national trade policies, including opposition to the Trans-Pacific Trade Agreement; Medicare for all; break-up of the big banks; tuition-free public college, and robust policies to combat climate change that include a ban on fracking and a carbon tax. Sanders has also championed more progressive taxation to pay for public investment in infrastructure, an end to mass incarceration, comprehensive voting reforms and curbs on big money in politics. On party rules, Sanders is ready to question the role and number of super delegates, those on campaign debates and their consistency in open and closed primaries. The question is how Clinton and her campaign will respond. One option is that she can demonstrate confidence in her leadership by celebrating the energy of Sanders’ youthful supporters and supporting some of his signature reforms. This would show, as she has said repeatedly, that there is “much more that unites us than divides us.” Successfully negotiating this challenge could help make Clinton more a candidate of change than one of continuity. Though President Barack Obama’s approval ratings are rising, surveys still show that 60 percent of voters want the nation to take a different direction than that under Obama, and only one-third want to continue his policies. Clinton could use her embrace of Sanders to highlight the changes she would champion. Alternatively, she could decide to shut down any Sanders challenge as part of a pivot to a more triangulated position in the general election. This is likely to produce a tempestuous convention, however, and stoke the anger of Sanders supporters. Sanders seems likely to force the issue in Philadelphia. His campaign stands ready to negotiate with Clinton about convention rules and the party platform. He is planning to debate the issues in committee meetings and on the floor of the convention hall. With his wins, Sanders expects a prime-time slot to address the convention, which would give him a platform to speak to the entire country. He will also likely continue rallying his supporters against the bigger threat of Trump. Clinton, meanwhile, would like Sanders to endorse her “without conditions,” as she says she endorsed Obama. (She made the endorsement only after Obama promised to help her retire some $22 million in campaign debts.) Clinton, the presumed nominee, will clearly have control of the convention. Her ally, Democratic National Committee Chairwoman Debbie Wasserman-Schultz, has stacked the platform and rules committees with Clinton supporters, which has earned a justified public rebuke from Sanders. Shutting Sanders out, however, would be the height of folly. He’ll come to the convention with more votes, more primary victories and a greater number of delegates — more than 1,500 — than any insurgent Democratic candidate in decades. More than Senator Edward M. Kennedy against President Jimmy Carter in 1980, or Senator Gary Hart against former Vice President Walter Mondale in 1984. Key blocs of voters — millennials and independents — have voted for him overwhelmingly. These followers will be particularly sensitive to how Sanders and his ideas are treated in Philadelphia. Sanders’ overall aim is to have the Democratic Party platform reflect his agenda. True, candidates often ignore the party platform. But it remains a measure of the party’s priorities and values. Sanders first step will likely be direct negotiations with Clinton — to probe what she is prepared to champion. He’ll want commitments on, for example, an executive order granting preference in government contracts to companies that pay a living wage with solid benefits, or on ending the tax loophole that lets hedge fund billionaires pay lower tax rates than their secretaries. Sanders has already moved Clinton left on trade issues. She has come out against Obama’s Trans-Pacific Partnership deal. She has also promised to sign a $15 an hour minimum wage bill and says she would never again allow Wall Street to threaten Main Street. She’s talked about regulating fracking tightly enough to make it virtually impossible. Her platform on reforming money in politics is essentially identical to Sanders’. But Sanders is still pressing her to support tuition-free public college, which she has mocked in the past. A broader program along these lines would certainly help her with millennials, who have voted against her in overwhelming numbers. Depending on convention rules, Sanders is likely to have enough delegates to bring some of his signature proposals before the entire convention. These might include Medicare for all, a carbon tax, a ban on Super PACs in Democratic primaries and breaking up the big banks. Many of Clinton’s delegates favor one or more of these proposals. The argument in the Republican Party has focused more on Trump’s character than his policies. The Democratic debate in Philadelphia will be on substance — the policies and priorities of the party and the direction of the country. That contrast alone is likely to give the nominee a boost headed into the general election. Robert L. Borosage is president of the Institute for America’s Future and co-director of its sister organization, the Campaign for America’s Future