Brian Snyder / Reuters

Bernie Sanders won’t admit defeat, but the presidential hopeful is signaling a clear shift in strategy.

After a string of primary contest losses in Northeastern states, Sanders vowed to stay in the race “until the last vote is cast.” Notably, however, he made no promise to actually win the presidential nomination in a statement released by the campaign on Tuesday evening. Instead, Sanders declared he would “fight for a progressive party platform” at the Democratic National Convention in Philadelphia this summer. The candidate ticked off a long list of items he wants to see in the platform, including a $15 hourly minimum wage, free admission for public colleges and universities, and support for a carbon tax as a way to fight climate change.

The Democratic candidate seems to believe that his best shot at a political revolution now rests with fighting to transform the party, and politics-as-usual, rather than winning the White House. As the campaign shifts into this new stage of the race, it may increasingly need to fight a two-front battle, with Sanders doing everything he can to maintain grassroots enthusiasm while working to effectively make the case for change to party elites.

A behind-the-scenes push to shape party politics appears to already be underway. The New York Times recently reported that “aides to Mr. Sanders have been pressing party officials for a significant role in drafting the platform for the Democratic convention.” But how much would it matter if Sanders is indeed able to shape the platform? It would be far less powerful than winning the White House, but that doesn’t mean it would be inconsequential. The convention could provide a high-visibility opportunity for Sanders to preach his message of political revolution. If he can influence the Democratic platform, that would provide tangible evidence of his success. A party platform that spells out many of Sanders’s political priorities could become a tool for activists to hold the party accountable and pressure Democrats to move in a more progressive direction.

The long-term success of the Sanders campaign hinges on the extent to which its message turns into conventional wisdom within the Democratic Party. A strong showing by Sanders at the Democratic convention and an impact on the party platform could further that goal. “I think Sanders is right that partys evolve in their thinking on issues and to the extent that particular priorities become institutionalized within the party that does have implications for the way that future candidates are going to act,” said John Sides, an associate professor of political science at George Washington University, in an interview. “The important thing is whether the priorities of the Sanders’s campaign and his supporters become fixtures of the party’s agenda.”

Still, whatever happens at the convention will only amount to one part of the equation. Whether the campaign’s articulated ambitions ultimately turn into law will also depend on the extent to which Sanders’s grassroots army, made up of supporters, allied networks and candidates who attempt to emulate his success, continue to mobilize to carry out his work. If Sanders wants to keep fighting for a more progressive party, he will need to keep his supporters engaged. What they say and do in the coming months will set the tone for what happens this summer as well.

At the same time, there is more risk than ever for Sanders if he alienates his rival Hillary Clinton and her allies. Sanders has felt increasingly empowered to level sharp criticism at Clinton, painting her as an establishment candidate who embodies the problems with the political status quo. But if he continues to make pointed comments, Sanders could come under pressure from Clinton supporters to exit the race, or face accusations that he is stringing along his supporters and acting in bad faith. If Sanders treads carefully, it would likely increase the odds that the Democratic Party will be willing to hear out his demands when it comes time to talk over the party agenda.

Sanders indicated he plans to run “issue-oriented campaigns in the 14 contests to come,” in the statement released by his campaign on Tuesday. It makes sense that Sanders would stick to his core messages of tackling income inequality, taking on the big banks, and reforming campaign finance, as he continues to campaign around the country. Those issues matter to his fans and will likely go a long way toward keeping them engaged. But without the drama that comes with running a highly competitive race, Sanders may need to do more to hold the public’s attention.

It’s impossible to say for sure what Sanders will do next. The candidate indicated to the Associated Press that he would continue to draw contrasts between his candidacy and that of Clinton’s. “Of course,” Sanders said when asked. “I’m getting attacked by Hillary Clinton and her surrogates every damn day.” He added: “A campaign means that you talk about your record, what you believe in, as opposed to your opponent's. That's what Clinton does. Of course we're going to do that.” A key question now is what Sanders has in mind when he says he will continue to draw a contrast. He will surely continue to focus on  issues where he and Clinton diverge, but how often and when will he invoke her name, and will he do so in ways that agitate her allies? Sanders has also indicated he won’t encourage his supporters to vote for Clinton anytime soon. He seems intent on not ceding any leverage, and determined to make Clinton work to win over his followers if she becomes the nominee rather than taking their support for granted.

The most obvious way Sanders could ensure that his supporters don’t lose interest while keeping Clinton and her allies at bay would be for him to more forcefully step up his attacks against Republican front-runner Donald Trump. Sanders routinely goes after Trump in his speeches, and recently told NBC he would “do everything that I can to make certain that Donald Trump is not elected president.” Escalating attacks against Trump would remind his supporters that the fight is far from over, and that there are very real stakes in the general election. Such a strategy would likely be welcomed by the Clinton campaign.

Whatever happens, it is increasingly clear that Team Sanders is thinking about how to lay the groundwork for a different kind of victory. The victory likely will not be one that lands their candidate in the White House, but it may be one that will influence the trajectory of liberal politics for years to come.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.