Michelle Bachelet, Chile’s president between 2006 and 2010, pulled off Sunday what no other Chilean president has done since the return of democracy in the post-Pinochet era — win a second, non-consecutive term.

To draw a contrast to the United States, only one president managed to return to the White House after leaving it — Grover Cleveland, who served two non-consecutive terms in the 1880s and the 1890s, though he’s routinely ranked among the more forgettable and inconsequential of US presidents.  Although it’s an inexact analogy (US presidents have never been barred from holding two consecutive terms the way that Chilean presidents are), Bachelet now faces the challenge of becoming one of Chile’s transformational 21st century leaders — in short, her challenge is not to become Chile’s Grover Cleveland.

Her return as president follows a four-year interregnum of government by Chile’s center-right — and in Sebastián Piñera, a president who represented the most moderate tendencies of the Chilean right, largely unsullied by association with the 17-year military regime of Augusto Pinochet.  Piñera’s term has been marked by relatively robust economic growth and sound government, even if Piñera himself hasn’t always been the most effective advocate for his own administration.  That became especially clear as Piñera seemed to lose control of the tussle between his government and student protesters throughout his term in office.

Moreover, the center-right did itself no favors in the process of nominating a candidate to succeed Piñera — the initial resignation of frontrunner Laurence Golborne last spring over private-sector scandal, the subsequent primary fight within the Chilean right between the more moderate Renovación Nacional (RN, National Renewal) and the more conservative Unión Demócrata Independiente (UDI, Independent Democratic Union), the sudden withdrawal of the primary winner Pablo Longueira, and his hasty replacement with former labor minister Evelyn Matthei as the standard-bearer of the fractured center-right Coalición por el Cambio (Coalition for Change) — widely referred to as the Alianza por Chile (Alliance for Chile).

But even in a parallel universe where a united Alianza backed a scandal-free Golborne, Bachelet was always deemed the favorite to win the Chilean presidency.  Furthermore, though Bachelet nearly routed Matthei in the first round (46.70% to 25.03%), she won a nearly two-to-win landslide against Matthei in Sunday’s runoff (62.16% to 37.83%).  But as Bachelet prepares to return to La Moneda, she should fear that the same forces that rendered the Piñera administration so unpopular could also render her second term even more  unpopular, especially after raising such high expectations in her successful second-term presidential campaign.

Part of the problem is that her constituency today covers a wider portion of Chile’s political spectrum than it did in her first victory eight years ago.  In her first run for the presidency, Bachelet represented the broad center-left Concertación de Partidos por la Democracia (Concert of Parties for Democracy) that ruled Chile between 1990 and Piñera’s inauguration in 2010, a coalition of three major parties, the Partido Demócrata Cristiano (PDC, Christian Democratic Party), the Partido por la Democracia (PPD, Party for Democracy) and Bachelet’s own Partido Socialista de Chile (PS, Socialist Party of Chile).  In her second run, however, Bachelet widened the coalition to form what she calls the Nueva Mayoría (New Majority), which brought several labor, Mapuche, student and other groups into the mainstream center-left, including perhaps most notably a merger with the hitherto isolated Partido Comunista (Communist Party).  Though it’s been a great strategy for building a winning coalition, it means more expectations from more corners of Chilean society.

Taken together with her longstanding wide margin for victory (a victory that became more likely with the Alianza‘s self-inflicted struggles), Bachelet led a Nueva Mayoría candidacy that promised more than any other presidential campaign in the post-Pinochet era — a new constitution for Chile, free student tuition within six years, major tax reforms (mostly in the form of corporate and income tax increases) and other legislative acts to roll back Pinochet-era laws and regulations.  That’s to say nothing about expectations that Bachelet will liberalize abortion laws in Chile (which remains one of the few countries in the world where abortion is illegal) and establish same-sex marriage.  In many cases, it remains unclear how Bachelet can accomplish much of her agenda.

In the first round of the election, which determined the composition of both the lower house of the Chilean parliament, the Cámara de Diputados (Chamber of Deputies), and one-half of the upper house, the Senado (Senate), Bachelet’s Nueva Mayoria won a solid majority (67 deputies out of 120 and 21 out of 38 senators).  But it’s not the four-sevenths majority that she will need for major reforms, let alone the two-thirds majority it will need for constitutional revisions.  While that may be due to Chile’s odd ‘binomial’ electoral system adopted by the Pinochet-era constitution, it’s an electoral system that is designed to guarantee that neither the left nor the right amasses an easy supermajority.

Another part of the problem is that much of the electorate seems fed up with both Chile’s mainstream left and right.  More than one out of four voters opted against both Bachelet and Matthei in the first round, turning instead to the progressive Marco Enríquez-Ominami, who has accused Bachelet of stealing his agenda, and the independent Franco Parisi, who captured the imagination of many conservative voters.

If there’s one lesson from the Piñera administration (and perhaps even from the first half of the first Bachelet administration, when Bachelet’s popularity plummeted dipped to around 35%, according to polls, before recovering to around 85% when she left office), it’s that the Chilean electorate is not easy to please.  For Bachelet, who has campaigned on vague bromides to reduce income inequality, she may find herself facing an increasingly skeptical public if she’s unable to deliver.  If the example of Piñera’s administration isn’t enough to scare Bachelet, she need only look to the intense decline in the popularity of France’s socialist president François Hollande just months after his own election.

The stakes are higher because the accomplishments of Bachelet’s career (and the popularity with which she ended her first term) will invariably be viewed through the prism of her second term’s success — or its failure.  Her first-term highlights include instituting a minimum pension for the lower 60% of Chileans, establishing gender equality laws with respect to wages, creating a Chilean sovereign wealth fund, creating Chile’s environmental ministry, navigating Chile through the global financial crisis, and shepherding the eventual success of the Transantiago public transport project in the Chilean capital.  That’s in addition to her success in enacting reforms to the public health care system — Bachelet, a former pediatrician, served as the health minister in the administration of former president Ricardo Lagos.

As the only country in Central or South America that is a member of the Organisation of Economic Co-operation and Development, Chile remains a lodestar for successful economic policy and political stability throughout Latin America.  That means that the standard for Bachelet remains higher than for other Latin American leaders — not only must she maintain the kind of economic performance expected of a model state, but Chile’s OECD accession has left many of its residents expecting a rise toward a North American standard of living.  So even as Bachelet attempts to enact the wide-ranging social transformations that she has promised throughout the 2013 campaign, Chileans will still continue to demand ever-higher economic performance.  

While Bachelet inherits a relatively strong economy from Piñera (which will likely continue so long as demand for copper remains robust), the lofty expectations both within her own Nueva Mayoría coalition and among the broader electorate should give Bachelet enough pause between now and her inauguration.