The Des Moines Register poll, long considered the gold standard in surveying the notoriously difficult to predict Iowa caucuses, puts Hillary Clinton at 45% and Bernie Sanders at 42% heading into tonight’s vote. A dead heat.

The caucuses are make or break for Sanders. With a win tonight, the Vermont Senator would have a narrow but conceivable path to the Democratic nomination. Without a win in Iowa, things become much more difficult.

Ahead of this crucial vote supporters of both sides have flooded my Facebook feed with arguments for one or the other. The debates are usually civil but occasionally heated.

I find myself agreeing with both sides.

In many cases, supporters of Hillary and Bernie are talking past each other. They highlight different and completely legitimate reasons to support their preferred candidate (and real weaknesses of the other), but they mostly miss or sidestep the larger disagreement between the two in terms of short-term and long-term goals and views of how change can be achieved.

Supporters of former Secretary of State Hillary Clinton are looking for a Democratic candidate who can win the election and then operate the levers of power with competence and poise. They see someone who has exceptional experience at the highest levels of politics, government and foreign policy and who has the grit to persevere against an almost-certainly hostile legislative branch. They see her as someone who can play the hand she is dealt and eke out small policy wins, bureaucratic advances and acceptable Supreme Court nominees using the familiar mechanisms of the presidency and, when necessary and possible, triangulation and compromise.

They see Sanders as well-intentioned but naive and untested and perhaps even temperamentally and ideologically incapable of taking the steps that will be required to secure incremental change.

These arguments for Clinton are well represented by a series of recent pieces by progressive pundits, many of whom I greatly respect, attempting to rein in support for Sanders with an appeal to practicality.

Paul Krugman, writing in his New York Times blog, for instance, argues that the contrasts between Clinton and Sanders’ plans on health care, financial regulation and other areas of public policy are “basically differences in strategy, not goals” and that Clinton’s strategies are far more realistic.

Sanders supporters see that same difficult political environment and make the case that far broader efforts are needed to overcome it. They argue that there is simply no way to get to universal health care, a political system not controlled by corporate interests, a real solution to climate change, compassionate immigration reform and many other foundational progressive policy goals (almost all of which Clinton and her supporters also endorse) without a movement to shift the boundaries of debate and change what’s considered possible.

They see Sanders as a Senator who has been both right and steadfast on issues of inequality and fundamental fairness for decades and is in a unique position to lead a movement and lead our country with an authentic voice and a strong moral compass.

They see Clinton as entrenched in the current political establishment and corporate power structure and worry that the kind of caretaker presidency she might lead, while it could achieve some incremental progress, would also enmesh us further in a broken system and waste a real opportunity for broader and more lasting change and a grassroots response to the radicalization of the right. And after her, then what?

Both camps claim the legacy of President Obama – Clinton as the architect of much of his foreign policy and inheritor of his strategy of small advances, often by executive order, in the face of Republican intransigence. Sanders offers a vision of what could have been if Obama had continued to engage with and mobilize his millions of supporters from 2008 instead of focusing all his time and energy on Sen. Olympia Snowe.

I agree with Sanders’ supporters that Clinton fails to focus on the long term. In fact, I’d go a step farther and say that Krugman and others are wrong: it’s not just the strategies but the goals themselves that are different. For instance, while Clinton says she believes that “affordable health care is a basic human right,” there is no mechanism in her public plans, no strategy, to get there.

This is important. There are incremental ways to get to universal coverage and even a single-payer system, like gradually lowering the age for Medicare, creating a public option or encouraging states to take advantage of the parts of the Affordable Care Act that allow them to pursue their own single-payer programs, but Clinton doesn’t propose any of these. On what her pathway would be to achieving that “basic human right,” she’s silent.

The path Sanders lays out is monumentally politically difficult, and basically depends on galvanizing the public and sweeping lots of conservatives out of office over the next few elections, but at least it exists.

(It’s also not completely without precedent. A self-declared democratic socialist leading a political revolution is what brought universal health care to Canada.)

I agree with Clinton’s supporters, however, that Sanders’ big ideas seem to be clouding his short-term vision. His policies on health care begin and end with broad strokes and assumption-heavy “Medicare for all” legislation, which would be dead on arrival in the almost certainly Republican held House of Representatives he would inherit upon assuming office. Are there no policy objectives he could pursue in this portfolio while his revolution kicks into gear?

This same dynamic between the candidates – short term vs. long term and laudable but difficult-to-achieve proposals vs. incrementalism that largely falls short of what’s needed – plays out in several other policy areas (the notable exception being gun safety, where the positions are pretty much reversed).

I would also agree with Clinton’s supporters that Sanders is untested. Who cares if he has better values, goals and policies, after all, if he doesn’t have the political skills to achieve them?

This point is perhaps most important in the context of the general election. November matchup polls at this stage are mostly useless, in part because Sanders has never faced the kind of unrelenting attack he would experience squaring off against a Republican nominee. We don’t yet know if he could muster the base of support necessary to beat Donald Trump, Sen. Ted Cruz or Sen. Marc Rubio, much less lead his proposed long-term political revolution.

For this reason, it’s helpful in a way for Democratic primary voters that Clinton’s campaign has opened up against Sanders in recent weeks. Facing off against her political machine is the first real test of his mettle and makes the stakes in Iowa tonight far greater than just the apportionment of the first few delegates. A win for Sanders would be an argument for the basic logic of his candidacy.

Whatever happens tonight and in the rest of the primary states, Democrats will have a candidate they are enthusiastically in favor of and who will stand in clear contrast to whichever nominee the racist demagoguery of the Republican process produces.

It also seems clear that, if either of them wins the democratic nod and then the presidency, the grassroots movement Sanders describes will still be necessary in order to achieve the kind of change they both say they support. Whether the president is leading that movement or simply taking advantage of what it makes possible in an incremental way, it will take far more than winning a nomination and winning a November election to address the big issues that underlie this primary contest.