“Inevitable.” That’s the word often used to describe Hillary Clinton and the 2016 Democratic nomination. Can anyone beat her? Anything’s possible, but the odds appear quite low. Still, her most threatening intraparty opposition could prove to be a man who isn’t even technically a Democrat (yet, anyway): independent Sen. Bernie Sanders of Vermont, a self-identified “democratic socialist.” We see him as a potential thorn in Clinton’s side, and to reflect that, we are moving Sanders to the top of the non-Clinton tier in our presidential rankings for Democrats.

Some progressive activists are still hoping Sen. Elizabeth Warren (D-MA) will get into the race. However, while she reportedly met with some members of the “Draft Warren” movement in late April, it still seems very unlikely that the Bay State senator will run. The idea of New York City Mayor Bill de Blasio (D) running, and doing so credibly, is even harder to fathom than a Warren candidacy: He's only less than a year and a half into his first term, and already he is controversial and has just a 44% job approval rating (according to Tuesday's Quinnipiac survey).

Sanders is in a position to fill the void to Clinton’s left, possibly attracting voters who are skeptical of Clinton because of her ties to Wall Street and her perceived hawkishness on foreign policy issues. Because of his issue positions and personality, Sanders could be an attractive candidate for liberals who want someone to press Clinton on topics like income inequality, free trade, and her Senate vote in favor of authorizing the Iraq War (although that vote is now more than a decade old).

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On the issues, Sanders was the third-most liberal senator in the last Congress, behind only Warren and Sen. Tammy Baldwin (D-WI). His presidential announcement speech highlighted his goal of creating “an economy that works for all people rather than a small number of billionaires” and denounced the role of money in politics, particularly the post-Citizens United campaign finance system. While a member of the House in 2002, Sanders voted against the Iraq War and is a leading opponent of the Trans-Pacific Partnership agreement and other free trade deals. He has also favored nixing the Keystone XL Pipeline project, a matter about which Clinton has remained publicly undecided. These are all positions that will win him support among progressive and labor groups.

But along with his policy views, Sanders’ personal characteristics may also make him a potent “protest” option for liberals in the Democratic primary. He is assertive and knows precisely what he believes in --and is unabashed in expressing himself. Moreover, Sanders is unlikely to have delusions of grandeur -- he knows he isn’t going to be the presidential nominee -- so he has nothing to lose by pushing Clinton hard.

Looking back at past presidential campaigns, a point of comparison for Sanders is Eugene McCarthy, the Democratic Minnesota senator and three-time presidential candidate. McCarthy ran against President Lyndon Johnson in the 1968 New Hampshire primary and stunned everyone by nearly defeating the incumbent. The outcome spurred Sen. Robert F. Kennedy to announce his own candidacy and led to Johnson’s stunning decision to not seek reelection. Like Sanders, McCarthy had an independent streak, and in fact McCarthy ran for the presidency in 1976 as an independent. Democrats are relieved that Sanders has personally pledged not to bolt like McCarthy and play a Ralph Nader-like role (a la 2000) in the 2016 general election campaign.

To some extent, Clinton may be okay with Sanders potentially becoming her most serious opponent. Clinton has long known that someone would emerge to make the Democratic primary battle at least a minimal contest for the media to cover. Additionally, plenty of party activists in the early states want some competition in the race. Why not have her main challenger be the very liberal Sanders, someone who will lack the resources and standing to truly threaten her? Clinton also knows that she will need the base to turn out heavily in November 2016, so she has already moved to the left on certain issues, most recently immigration. Whereas someone like ex-Gov. Martin O’Malley (D-MD) fits the profile of a more serious challenger to Clinton (or did at some point), Sanders is a senator from one of the smallest states, is unknown to most Americans, and cannot defeat Clinton, barring incredible unforeseen circumstances.

Speaking of O’Malley, his stock has tumbled in light of the recent events in Baltimore, where he served as mayor prior to becoming governor of Maryland. Criminal justice policies he implemented as mayor, such as zero-tolerance policing, have come under fire from critics who believe they contributed to the long-term problems undergirding the recent riots in Charm City. O’Malley has said he would announce in Baltimore “if” he runs for president, a very likely move at this point, but this location won’t provide an ideal campaign backdrop. Although he has to own and defend his record as mayor and governor if he’s to remain a credible candidate, Baltimore’s unrest can and will be used against O’Malley. For the time being, he is positioned behind Sanders in our rankings.

While we have shifted our Democratic rankings this week, we also have one change on the Republican side of the ledger: Gov. Rick Snyder (R-MI) announced last week that he will not seek the 2016 GOP nomination for president, meaning that we can again remove him from the Crystal Ball list. We had actually taken Snyder out of our rankings weeks ago but brought him back in our last Republican update because of numerous reports suggesting he would run. But now that he’s explicitly said he won’t, “one tough nerd” exits our rankings. That leaves a still-staggering 19 names on our Republican list, which you can see here.

Our Democratic rankings are below in Table 1.

Table 1: Crystal Ball rankings of Democratic presidential candidates

First Tier: The Undisputed Frontrunner Candidate Key Primary Advantages Key Primary Disadvantages Hillary Clinton

Ex-Secretary of State •Very popular within party, more so than in ’08

•Pro-Iraq War vote fading in importance

•Woman: chance to make history

•Dominant position scaring off other top Democrats

•Positioning self to avoid being outflanked on her left •Age (69 by Election Day ’16)

•Ran unfocused, too-many-cooks ‘08 campaign; could make similar mistakes in ’16

•Keeping Bill in check — and on the porch

•Scandals already emerging

•What policy rationale is there for a new Clinton presidency? Second Tier: Nobody

EMPTY — Clinton stands apart Third Tier: The Others Bernie Sanders

Senator (Ind.),

VT •Left loves him

•Small-donor fundraising potential

•Gadfly: Plenty of freedom because he has little chance of winning •Not actually a Democrat

•Outsider in what is very much an insider process

•Gadfly: Few expect him to win so will voters take him seriously? Martin O’Malley

Ex-Governor, MD •Liberal record and policy achievements

•Starting to show willingness to mix it up with Clinton •Baltimore baggage

•Chosen successor lost Maryland governorship

•Nationally unknown Jim Webb

Ex-Senator, VA •Unique populist niche

•Strong military background with Democratic views •Not liberal enough

•Unpredictable

•Not the best stump speaker Lincoln Chafee

Ex-Governor,

RI •Voted against Iraq war

•Willingness to attack Clinton •Never elected as a Democrat

•Left office very unpopular

•No base of support in party, nationally unknown The Wild Card Joe Biden

Vice President •Vast experience

•VP bully pulpit •Age (73 by Election Day ’16)

•Gaffe machine

•Poor presidential campaign history

Geoffrey Skelley is the Associate Editor at the Center for Politics at the University of Virginia.

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