The Democratic primary race, with more than half the delegates still in play, is now between Bernie Sanders and Joe Biden. They have radically different policy platforms and political strategies, but for many voters, the most pressing concern is which of these two men has the best shot of beating Donald Trump in November.

Fundamentally, we worry that Biden is not running an inspiring campaign that can win. His message to struggling young people is “give me a break” — things aren’t so bad. His message to climate activists and immigration activists who challenge his positions is “go vote for someone else.” And his message to Wall Street is “nothing will fundamentally change.”

The only Democrat to win the presidency since Bill Clinton was Barack Obama. Obama ran significantly to Hillary Clinton’s left in the primary, inspiring a generation with his vague but uplifting message of “hope and change.” Moderate Democrats who didn’t run inspiring campaigns, such as Al Gore, John Kerry, and Hillary Clinton, didn’t fare well.

Bernie Sanders, like Obama, has built a massive grassroots campaign with hundreds of thousands of enthusiastic, largely young, volunteers. This volunteer base will be critical when it comes time to register new voters, including young people, Latino voters, and working-class people who can swing elections in states like Ohio, Pennsylvania, and Michigan (where, despite Biden’s primary victory, voters under fifty preferred Sanders by overwhelming margins).

Joe Biden has no such volunteer base. He also has unique weaknesses that Trump will relentlessly exploit. Biden’s son, Hunter, was at the center of the failed impeachment proceedings against Trump. Trump will tirelessly pivot the campaign spotlight toward this issue, using it to fire up his base around their favorite issue: the alleged corruption of Democratic Party elites.

Biden’s vulnerability on this subject runs the risk of being an eerie replay of Hillary’s email “scandal.” And Trump has already begun to attack Biden’s record on working-class issues like cutting Social Security, supporting NAFTA, and voting for the Iraq War, and will continue to do so through the general election.

Joe Biden’s other positions make him unpopular with young voters who must turn out to beat Trump. His climate change plans are inadequate to the scale of the emergency. He wouldn’t forgive student debt, which has burdened a generation of Americans. And he wouldn’t use an executive order to close the inhumane detention centers on the US-Mexico border on his first day in office, as Sanders would. Sanders’s program, on the other hand, is firmly rooted in a vision of economic rights for all Americans, and his platform is resoundingly popular with voters of all ages.

Despite his many weaknesses, Joe Biden has been cast by the Democratic party establishment and sympathetic media as the “safe bet” with the best chance of beating Donald Trump. Many believe he isn’t polarizing like Sanders. He won’t rock the boat with calls for a “political revolution” during a fragile political moment. This narrative, as enticing as it may seem, is simply not borne out by the data.

A New York Times op-ed by Steve Phillips used polling data and evidence from the early primaries to show that the Bernie coalition has a viable pathway to victory. As Phillips and others have shown, Bernie consistently beats Trump in national head-to-head polls.

More importantly, Bernie has performed better against Trump than Biden in polls in key battleground states such as Michigan and Wisconsin. And in Pennsylvania, one Expedition Strategies poll shows both Biden and Sanders beating Trump, but a Morning Call poll shows Sanders up by three points and Biden tying Trump. Exit polls in states like Minnesota and North Carolina show that swing voters prefer Sanders to Biden. Although it’s hard to say that these polls are by any means conclusive, they suggest an edge that could matter in the general election.

In addition to having an edge over Biden in critical Rust Belt states that Trump won in 2016, Bernie Sanders has activated voters with historically lower turnout in recent primaries, such as young and Hispanic voters. He has also done well with young black voters, despite Biden doing well with older black voters in the Southern states that are likely to vote Republican in the general election.

Historically, black voter turnout is high in general elections, while Latino and youth voter turnout is low. Latino turnout, in particular, has been extremely low historically. Enthusiastic support for Sanders among Latino voters, as evidenced by high turnout in California and Nevada, will be vital in battleground states, potentially putting the erstwhile GOP stronghold of Arizona into play. Additionally, some believe that due to Sanders’s appeal to Latino voters, Texas could be in play in the general election as well.

These are voters who do not enthusiastically support Joe Biden, and the Democrats would be wise to not take their support for granted. There is no evidence that Joe Biden can turn out these demographics in a general election, and his uninspiring message is likely to dissuade these voters from coming out on election day at all.

Nominating Sanders, on the other hand, would allow the Democratic Party to fully leverage the largest field-based campaign infrastructure in the country to register new voters and make sure they are ready to go to the polls in November. These field-based tactics can make or break a general election. Bernie Sanders is uniquely positioned to deploy them, in the same way that Obama did, but Gore, Kerry, and Hillary Clinton could not.

As the coronavirus pandemic spreads, Trump has moved from denial to incompetence and malpractice. Biden has called for free testing, but has stopped short of calling for universal relief and care. This crisis will test not only society’s institutions, but also our larger worldview as a country, as it has revealed the vulnerability of our economic system and social safety net. With the spread of the virus, Sanders’s vision and program is best equipped to respond to both a public health and economic catastrophe. And the coronavirus represents both.

Sanders has called for a moratorium on utility shutoffs and evictions, and has called for emergency unemployment benefits for precarious workers. This escalating situation highlights the clear contrasts between Sanders and Biden, and Biden’s uncompelling strategy for addressing this crisis may prove to be a tremendous liability in November.

Due to Biden’s easily exploitable vulnerabilities and Sanders’s specific strengths, we know that Bernie is the safe bet to beat Trump. Biden is arguing to restore America “back to normal,” but after the damage of the Trump era, and now a global pandemic that may be a harbinger of crises to come, there may be no normal to return to. Biden is a weak candidate who is more likely to lose to Trump than Sanders. The best chance we have at ousting Trump is voting for Sanders in the primary.