Bernie Sanders and Eliz­a­beth War­ren have some­thing in com­mon: Both believe they are unique can­di­dates with dif­fer­ent pol­i­tics and agen­das—a point both have made clear in count­less inter­views and pol­i­cy pro­pos­als. And both believe these dif­fer­ences are worth fight­ing for, which is why both are run­ning for president.

Historically, such calls for unity and cooperation have required the Left to surrender to the status quo.

I agree. Specif­i­cal­ly, I sup­port Bernie Sanders and his call for a polit­i­cal rev­o­lu­tion, which has inspired mil­lions of Amer­i­cans to fight for his unique vision. I back Sanders because his sig­na­ture health­care plan, Medicare for All, would do what Warren’s would not: bring sin­gle-pay­er to Amer­i­ca in a sin­gle bill. I back Sanders because his Green New Deal pledges twice the funds War­ren pledges for inter­na­tion­al adap­ta­tion and mit­i­ga­tion. I back Sanders because his hous­ing plan calls for nation­al rent con­trol and three times as much afford­able hous­ing as Warren’s. I back Sanders because on issue after issue — from for­eign pol­i­cy to labor pol­i­cy to a more aggres­sive wealth tax — he is fight­ing for an agen­da in a com­plete­ly dif­fer­ent league from any of his Demo­c­ra­t­ic rivals. With a move­ment at his back, I believe Sanders can win.

But through­out the pri­ma­ry sea­son, Sanders sup­port­ers have encoun­tered calls for ​“uni­ty” and ​“coop­er­a­tion” with his rivals, par­tic­u­lar­ly with War­ren. For two rea­sons, Sanders sup­port­ers should view these calls with skepticism.

First, calls for the Sanders cam­paign to coop­er­ate begin with the premise that Sanders can­not win a major­i­ty of del­e­gates—which may feel true, as Sanders has only briefly placed first in nation­al polling. His­tor­i­cal­ly, how­ev­er, such pes­simism is unfound­ed. At this point in 2004, John Ker­ry was polling nation­al­ly at 5%, trail­ing Howard Dean, Wes­ley Clark, Dick Gephardt and Joe Lieber­man. In Jan­u­ary 2008, Barack Oba­ma was polling in the mid-twen­ties — 20 points behind Hillary Clin­ton. In both cas­es, the even­tu­al nom­i­nee over­came heav­i­ly favored rivals by win­ning ear­ly state vic­to­ries and build­ing enough momen­tum to cap­ture a major­i­ty of delegates.

Here is the posi­tion that Sanders finds him­self in today: polling well ahead of where Ker­ry was in 2004, bet­ter posi­tioned against Biden than Oba­ma was against Clin­ton in 2008, and cur­rent­ly fight­ing for first in Iowa, New Hamp­shire and Neva­da. That’s why the New York Times, Politi­co and Van­i­ty Fair recent­ly con­ced­ed: Bernie Sanders could win the nom­i­na­tion. So why should his cam­paign hedge its bets or pull its punch­es? Sanders has a win­ning mes­sage and he should work to expand his rel­a­tive­ly poor, diverse and youth­ful base by mobi­liz­ing even more uncom­mit­ted vot­ers — and by mak­ing inroads into oth­er coalitions.

Which rais­es the ques­tion: Why would so many pun­dits, often pro­fess­ing sym­pa­thy for Sanders, argue he can­not win and should not com­pete with his rivals — specif­i­cal­ly, with War­ren? No doubt many of these calls are made in good faith, if only because the lib­er­al-left is often reflex­ive­ly pes­simistic and deeply sus­pi­cious of sectarianism.

Still, there is a sec­ond rea­son why Sanders sup­port­ers should be skep­ti­cal: His­tor­i­cal­ly, such calls for uni­ty and coop­er­a­tion have required the Left to sur­ren­der to the sta­tus quo. When advo­cates for uni­ty in the Demo­c­ra­t­ic Par­ty say ​“we want the same thing,” what they often mean is that they don’t con­sid­er our par­tic­u­lar caus­es worth fight­ing for. When they call for ​“coop­er­a­tion,” what they want is for us to stop telling hard truths and mak­ing ​“unre­al­is­tic” demands.

There may come a time dur­ing the pri­maries when it makes sense for Sanders to bar­gain with his rivals, as he did in 2016. Until then, the win­ning strat­e­gy is the most straight­for­ward: Sanders should try to win as many del­e­gates as pos­si­ble, which will max­i­mize his nego­ti­at­ing lever­age if it doesn’t win him the nom­i­na­tion. This means com­pet­ing with Joe Biden, Pete Buttigieg and, yes, Eliz­a­beth Warren.

The views expressed in this piece are the author’s own. As a 501©3 non­prof­it, In These Times does not oppose or endorse can­di­dates for polit­i­cal office.

For anoth­er per­spec­tive, read We Need Sanders and War­ren To Coop­er­ate In the Pri­ma­ry by Julian Brave Noisecat.