Why Hasn't Elizabeth Warren Taken Sides?

U.S. Senator Elizabeth Warren takes part in the Washington Ideas Forum in Washington, D.C., on October 1, 2015. Jonathan Ernst/Reuters

This article first appeared on The Conversation.

Massachusetts Senator Elizabeth Warren is the most sought-after endorsement in the raucous Democratic presidential primary contest.

It's all bit odd for a senator who has been in office only since 2012 and who beat incumbent Senator Scott Brown by just 10 points as Massachusetts went for Barack Obama over its own former Republican governor, Mitt Romney, by a much wider margin—23 points.

And as any political scientist will tell you, the capacity of one key endorsement to move votes is complicated at best.

So why then do Bernie Sanders and Hillary Clinton adherents so want an Elizabeth Warren endorsement?

The answer is simple: Warren is the unifying voice for Democrats. She is the trusted arbiter who could make the other side "see the light" and rally around the party's eventual nominee.

No Love Lost

Right now, among the hard-core party loyalists who are most likely to vote in primaries, there is no love lost between Bernie and Hillary supporters:

"He isn't even a Democrat!"

"He has one issue—class politics—and can't talk foreign policy!"

"She embodies how the Democratic Party went wrong by going corporate!"

"She is not trustworthy!"

And those are the substantive critiques. Scroll down in article comment sections if you dare.

Elizabeth Warren appeals to both the Sanders and Clinton camps. And importantly, she is holding on to the power to bring them together by remaining silent on an endorsement.

More to Gain by Remaining Silent

If Warren were to endorse Clinton, Sanders supporters would have to take seriously that Warren, the leading analytic and elected voice on "how the system is rigged"—the person who publicly named and effectively shamed credit card companies, mortgage lenders and student loan providers—does not see him as the standard-bearer of this fight.

It would lend legitimacy to the notion that while Warren may see Sanders as most ably analyzing the sources of downward economic mobility, real questions exist as to how he could manage the whole of the presidency and connect with communities of color given the South Carolina results.

If Warren were to endorse Sanders, Clinton supporters would have to consider how a leading woman of roughly the same cohort as Secretary of State Clinton parted ways with her and what that means for Clinton's ability to truly take on Wall Street.

A Sanders endorsement also turns Clinton's willingness to deal on policy from a governing strength to a character flaw that would spell doom for progressive causes—especially on economic equity.

Deafening and Golden

Senator Warren has not endorsed, then, because her silence is more powerful.

Withholding support from Clinton signals that Clinton must meaningfully and substantively go left on economic policy. It does so without harming Warren's own high marks from the Sanders crowd.

Warren's silence also preserves her ability to be the "uniter" among the warring wings of the Democratic Party come convention time.

Supporters of both Clinton and Sanders will be disappointed Warren did not come their way earlier, but this summer in Philadelphia her alignment with the eventual Democratic nominee will help tell the losing faction, "It's OK to come home."

Erin O'Brien is an associate professor of political science at the University of Massachusetts Boston.