If there is a role in American political life more powerful than being a freshman senator in the minority party, chances are liberal groups want Elizabeth Warren to occupy it. And, sure enough, Democracy for America and the Progressive Change Campaign Committee are already signaling support for a Warren run to succeed Harry Reid as Senate minority leader, challenging Reid's pick, Chuck Schumer.
Warren's office says she won't run, which is exactly the right call. Making Warren majority leader wouldn't actually serve DfA or PCCC's goals. It wouldn't move the party meaningfully to the left. Rather, it would move Warren to the right, and it would sacrifice the most effective outside voice pushing for the caucus to adopt a more economically populist agenda.
Democrats have a tendency to underrate the value of outside pressure, but it's hugely important, especially if you want to move the center of the party. House conservatives have been enormously effective in pushing John Boehner to demand more of the White House, and have trillions in spending cuts to show for their efforts. Warren has the potential to be that kind of force in her party, to effect a leftward move among Democrats as a whole. But she can only do that if she doesn't become leader.
The party decides
If you want to know what would happen to a Minority Leader Warren, consider what happened to Nancy Pelosi after she took the reins of the House Democratic caucus in 2003. Before ascending to the leadership, Pelosi was among the most liberal members of the entire House. She represents San Francisco, after all. She was a founding member of the Congressional Progressive Caucus, opposed Bill Clinton's welfare reforms, and cosponsored Rep. Marty Russo's (D-IL) 1991 proposal for single-payer health care.
She's still quite liberal on a personal level, telling Vox's Ezra Klein last year, "Of course I wanted single-payer" during the health reform fight of 2009–2010. But she's a party leader. She needs votes from Southern blue dogs and more moderate liberals, like her deputy Steny Hoyer, to get anything done, especially in 2009–2010 when her majority was held together by congressmen elected from usually Republican districts. That means compromising. It means settling for the policy preferences of the median member of the party. It means pushing the caucus to be even more conservative than it wants to be on some occasions, as in early 2010 when Pelosi got House Democrats to agree to the Affordable Care Act, the Senate's less ambitious response to the Affordable Health Care for America Act that the House had passed in November 2009.
As Matt Yglesias notes, a similar thing happened to Harry Reid — though in the reverse direction. Reid represents Nevada, a purple state, and is personally anti-abortion. In a 1998 survey, he stated that he believed abortions "should be legal only when the pregnancy resulted from incest, rape, or when the life of the woman is endangered." That's obviously at odds with his party — so Reid started fighting for abortion rights. In recent weeks alone, he's worked to block a human trafficking bill because it doesn't allow victims of trafficking to use money seized from perpetrators to get abortions, and is objecting to a "doc fix" bill Pelosi and John Boehner crafted because it prohibits the use of community health center funds for abortion.
The value of being on the outside
Warren isn't technically on the "outside" of Senate leadership anymore — after the 2014 election, she was appointed to be "strategic policy adviser to the Democratic Policy and Communications Committee." But let's be real: that's not a super-important position. Strategic policy advisers to the Democratic Policy and Communications Committee seldom make history. What's more, Warren's actual role in the leadership is to serve as a liaison to and advocate for progressive groups. She's the inside's official outsider.
And being on the outside has its perks. Just think about how many fights Warren has pitched against President Obama and other congressional Democrats in recent months. She killed Obama's nomination of Antonio Weiss, an investment banker, to be undersecretary of the Treasury. She recently went to war with the administration over the big East Asia trade deal it's negotiating. She tried to block the CRomnibus spending deal in December over its changes to the Dodd-Frank financial reform act.
You just can't be that antagonistic toward a president of your own party when you're a congressional party leader. You can disagree behind the scenes, and on rare occasions you can choose to pick a public fight, but you can't mobilize the kind of grassroots opposition that Warren routinely relies on. The last time a president and Congress of the same party were that at odds was during Jimmy Carter's presidency, and the result was that Carter left office with no domestic achievements to speak of.
But again, there's value for liberal groups in having a charismatic liberal senator working to push the Overton window to the left. Antonio Weiss got another, non-Senate-confirmable job at Treasury, but Warren really did force him out of the undersecretary job. And as House Republicans have demonstrated, there's value in having strong ideological factions within parties, both for the factions and for the parties as a whole. The right flank of the House GOP strengthened John Boehner's bargaining position vis-à-vis the White House by letting Obama know there was an implacable portion of the House Boehner couldn't control that wouldn't come along unless the president made real concessions. And so Obama made real concessions.
If liberals want Warren to lead a group of senators, it should be other liberal senators — folks like Sens. Bernie Sanders (I-VT), Sherrod Brown (D-OH), Tammy Baldwin (D-WI), and Jeff Merkley (D-OR). If the grouping were large enough, it could exert the kind of influence House conservatives have, and limit the concessions Reid and whoever succeeds him can make. If a Republican president succeeds Obama, it would create a dynamic parallel to that of Boehner and the House conservatives in 2011 — you can decide for yourself if you think that's a good idea.
That plan might fail. It might be that there just aren't enough committed left-flank Democrats willing to engage in such an effort. But it's a more promising strategy than joining the leadership and abandoning the considerable influence Warren already wields.