Bernie Sanders continues to perplex pundits. Why is he still in the race, given that he’s sure to lose to Hillary Clinton and, some argue, should be helping the Democrats unite to defeat Donald Trump? Over the weekend, Edward Luce in the Financial Times suggested that Sanders is “the ghost of Ralph Nader”: a spoiler who will make an independent bid which will destroy the Democrats. Earlier, Josh Marshall in Talking Points Memo suggested that the “toxicity” of the Democratic primaries was driven by Sanders’s unwillingness to “let it go.” Both theories imply that Sanders is the type to let his vanity derail the Democrats and elect Trump.

But what if Sanders isn’t a Nader-type spoiler or a losing candidate in denial about the inevitable, and instead has his own theory as to how to defeat Trump? Sanders is staying in the race in part to gain greater leverage to push the party to the left, but this ideological motive is not disconnected from realizing that Trump is a menace.

Part of the difference between Clinton’s liberalism and Sanders’s leftism is their differing views on how best to defeat Trump. Clinton has already indicated that her strategy includes wooing moderate Republicans, including donors, who are disaffected because of Trump. This approach goes against Sanders entire raison d’être as a candidate: to prove that Democrats can win elections by running on progressive platforms and relying on small donors.

The Trump threat is being used as a cudgel to convince Sanders to give up his campaign. A series of new polls show that Clinton and Trump are virtually tied in a head-to-head matchup: According to an NBC/Wall Street Journal poll, Clinton has only a three-point advantage (46 percent to 43 percent), while a Washington Post/ABC News poll has Trump with a two-point lead (46 percent to 44).These numbers reflect the fact that Republicans have consolidated behind Trump while Democrats remain divided: Liberal independents, a key Sanders demographic, are hesitating to say they support Clinton against Trump. The New York Times’s Nate Cohn noted that “Bernie Sanders’s supporters are a big reason Clinton is doing worse in her polling against Trump. In the recent YouGov poll, Clinton had just a 40-point lead against Trump among Sanders voters, while Sanders had a 70-point lead. Trump was getting virtually the same share of the vote against both candidates—40 percent against Clinton, 39 percent against Sanders. Presumably most Sanders supporters will ultimately get behind Clinton.”

Sanders isn’t prepared to surrender just yet, but the hyperventilation of some Clinton supporters and the worry that he could spoil her chances are completely unfounded. In fact, close attention to his recent moves reveals that Sanders is carefully trying to thread the needle of acknowledging that Clinton is the nominee while also securing a greater voice for his progressive politics in the Democratic Party, particularly by making a push to reshape the Democratic National Committee and the party platform, which will be hammered out in Philadelphia.

As reported by Sahil Kapur in Bloomberg, Sanders has privately reassured Senate colleagues that he’s going to support Clinton when she’s the nominee. While campaigning in California over the last few days, Sanders made a significant shift in his stump speech, erasing his standard critique of Clinton and focusing almost exclusively on criticizing Trump. Significantly, former Sanders advisers such as Zack Exley have drafted a document outlining the case for conceding to Clinton and securing Sanders’s political revolution in the party by working for progressive down-ballot candidates.

The strategy outlined by his former staffers would involve Sanders’s giving up his outsider status and becoming a full-blown Democratic kingmaker. As Clinton supporters like to point out, Sanders has long self-identified as an independent and only started declaring himself a Democrat when he decided to run for the nomination. Yet if he is to have a lasting legacy, it’ll be as someone who remade the party he spent most of his life keeping at arm’s length. By running an unexpectedly strong campaign, Sanders has become a Democratic wheeler-dealer, a bigwig in the party whose establishment he loves to rail against. It’s this paradoxical situation that will dictate the closure of his campaign: He’s preparing to support Clinton, but only at the price that the party gives him and his followers a seat at the table.

There’s evidence that this strategy is already paying off. The Democratic National Committee has already conceded that Sanders will have a stronger say in party platform than most losing candidates do: He was given the power to pick five of the 15 members of the committee that will write the party platform; his choices are notably left-of-center, including philosopher Cornel West and Congressman Keith Ellison. (Clinton gets six members, and the remaining four will be picked by DNC Chairwoman Debbie Wasserman Schultz, whose is facing a primary challenge in her home district by Sanders-backed Tim Canova.) With his committee picks, Sanders is hoping to push the party to adopt some of his signature policies. As reported by Greg Sargent in The Washington Post:

Some things the Sanders camp will push for include firm opposition to a vote on the Trans-Pacific Partnership in this Congress; requirements to break up too-big-to-fail financial institutions; more in infrastructure spending; a $15-per-hour minimum wage; tuition-free public college, and, possibly, a carbon tax, in keeping with the ambitious agenda Sanders has campaigned on.

These maneuvers will push the party left, but also make sense in terms of the larger goal of defeating Trump. Sanders supporters often point out that he does better against Trump in the polls than Clinton does. There’s some truth to this—he beats Trump by 54 percent to 39 percent in the NBC/WSJ poll—although it ignores the fact that the most damaging attacks against Sanders, related to his older far-left politics, have never been made nationally. This point is moot, though, since it is virtually impossible for Sanders to win the Democratic nomination. But if he won’t ever have a chance to face Trump, he can still help the party defeat the Republican demagogue. If Sanders has any say in it, the Democrats won’t make the centrist case against Trump, but an openly progressive one. And by staying in the race, Sanders has ensured that he does indeed have a say in it.