Claudia Sheinbaum won a landslide victory to become the first female president of Mexico and first Jewish person in the role, adding to the growing list of accolades to the climate scientist and former mayor of Mexico City.

But when she formally takes office in October, how will she tackle the biggest challenges facing the country as concerns about its security and the future of its democracy loom large?

Complicating her administration’s debut, Sheinbaum will also have to contend with the shadow of her polarizing mentor, the outgoing President Andres Manuel López Obrador, from the same Morena party.

Sunday’s vote was widely seen as a referendum on López Obrador’s term. And while his popular social welfare policies have helped push many Mexicans above the poverty line, experts say his security measures have done little to address the expanding reach of organized crime in the country.

In a speech following the election, Sheinbaum promised to govern for all and to be an investor-friendly president.

“We know that dissent is part of democracy. And although the majority of the people support our project, our duty is and will always be to look after each and every one of the Mexicans without distinction,” she said as she struck a conciliatory tone at the end of the highly partisan race.

“So, although many Mexicans do not fully agree with our project, we will have to walk in peace and harmony to continue building a fair and more prosperous Mexico.”

She promised a government “without corruption or impunity” and guided by “republican austerity, financial and fiscal discipline and autonomy of the Bank of Mexico.”

A victory for the Morena party

While Sheinbaum’s victory was widely expected this weekend, the “biggest story of last night” was that the Morena party looked set to gain supermajorities in both houses of Congress, said Carin Zissis, a Mexico expert, and editor-in-chief of the Americas Society/Council’s online magazine.

On Monday morning, the Mexican peso slipped roughly 3% against the US dollar amid rising concern that the ruling party will have a clear path to pass controversial constitutional reforms sought by López Obrador.

The reforms include a range of issues in areas like pensions and the energy sector, but they also include controversial judicial and institutional reforms, which critics say would weaken the separation of powers and see the disappearance of some independent regulatory agencies.

“We have to see what happens when she comes into office: There has been a history of Mexican presidents breaking the path of their predecessors, even when their predecessors more or less selected them,” Zissis said, adding: “Though, [Sheinbaum] has pledged throughout her campaign to continue his legacy.”

López Obrador has pushed back on suggestions that he would be giving Sheinbaum cues, saying on Monday that he would not “influence” his protégé. Sheinbaum is now “the one empowered to make all the decisions,” he said.

One of Sheinbaum’s biographers, journalist Jorge Zepeda, has speculated that, once in office, Sheinbaum will unfurl her own platform gradually: she will first act as “the faithful disciple of the leader,” before offering “glimpses” of her own program, taking care not to stoke instability in the movement’s base.

Gang violence and security

Violence has dominated this year’s election, with dozens of candidates murdered in the run-up to the vote and gangs trying to influence who was coming to power.

Sheinbaum inherits a tragic epidemic of unsolved disappearances in the country: More than 100,000 Mexicans and migrants have disappeared, with no explanation of their fate for families. According to the think tank Mexico Evalua, around 95% of all crimes nationwide went unsolved in the country in 2022.

Mexico also remains a dangerous place to be a woman and is “sadly, known for high levels of femicide gender-based violence where the number of disappeared women has gone up and up year to year,” Stephanie Brewer, Mexico Director at the Washington Office for Latin America (WOLA), told CNN.

With security at the top of voters’ concerns, Sheinbaum has pointed to her record as Mexico City mayor, with her team crediting her for improvements to the police’s pay, working conditions and intelligence-gathering capabilities – although there is some debate as to how much impact these measures had on bringing down the crime rate, experts said.

But will Sheinbaum’s tactics as mayor of Mexico City be replicable at the federal level and in Mexico’s 31 states, home to more than 126 million people? She will have to tackle a landscape where criminal groups have expanded their reach.

An hour away from Mexico City, in the state of Morelos, Will Freeman, a fellow at the Council on Foreign Relations, said he was told that organized criminal groups had “their own political candidates” in the town of Cuautla who could rely on armed wings to intimidate other people.

Gangs in the country have also diversified to sectors beyond the illicit manufacture of drugs. “They’re doing illegal logging, illegal mining. They’re taking control of the water supply, which is increasingly scarce,” Freeman said.

López Obrador’s term saw the expansion of the militarization of public security to tackle crime, a two-decades-long approach that has coincided with historically high levels of homicides.

A May report by the Crisis Group found official corruption and collusion was hampering effective law enforcement. (CNN has yet to receive comment from Mexican Secretary of Defense and the president’s office over the findings.)

Sheinbaum has largely remained coy about her security programs, but has said “that at the national level we can advance even more in terms of security,” she said in a tweet on X, which listed out her security strategy that included the consolidation of the National Guard, strengthened intelligence and research, and better coordination between the police, state prosecutors’ offices and the attorney general’s office.

Where Washington and Mexico City meet

Sheinbaum has previously signaled the importance of the US-Mexico relationship, especially around trade. “With the United States there will be a relationship of friendship, respect, mutual respect and equality as it has been until now, and we will always defend the Mexicans who are on the other side of the border,” she said late on Sunday, local time.

But analysts note there will probably be differences between US and Mexico when it comes to foreign policy. Sheinbaum is from the ideological and political left, and “I think she will be as friendly as López Obrador towards Cuba, Venezuela, Nicaragua [and] will not probably take the geopolitical positions the US would hope for” over Gaza and Ukraine, Freeman said.

López Obrador has angered advocates on both sides of the Israel and Gaza conflict. Mexico has ruled out breaking diplomatic relations with Israel, in contrast to some of its Latin American counterparts, but it has also sought to join South Africa’s genocide case against Israel.

Sheinbaum condemned the violence following Hamas’ October 7 attack on Israel and has previously called for a Palestinian state.

In a 2009 letter to the editor of a Mexican newspaper, Sheinbaum wrote that many of her relatives from her grandparent’s generation “were exterminated in the concentration camps.” She added that “because of my Jewish origin, because of my love for Mexico and because I feel like a citizen of the world, I share with millions the desire for justice, equality, fraternity and peace, and therefore, I can only see with horror the images of the state bombings,” referring to an Israeli bombing campaign of Gaza that year.

“No reason justifies the murder of Palestinian civilians,” she wrote in La Jornada.

A partner to the US on migration?

Sheinbaum will assume office just a month before Americans head to the polls in November, where immigration is a top issue on the ballot for candidates President Joe Biden and former President Donald Trump – both of whom have relied heavily on Mexico to step up immigration enforcement and help stem the flow of migration to the US southern border.

While migration across the countries’ 1,933 miles long border is a shared concern, migration is not a major issue among Mexican voters, Zissis said.

Still, under López Obrador, the Mexican government has accepted US deportations of tens of thousands of non-Mexican citizens under a 2023 Biden administration rule. López Obrador’s administration also stepped up efforts to block the path of migrants heading to the US by transporting large numbers of people from the north of Mexico to the south.

But while Mexico’s policies may have become a “major factor” in reducing some migrant crossing at the United States’ southern border, Brewer said it is “not a sustainable model for anyone” – especially not for migrants who are often targeted for violence in Mexico.

Will Sheinbaum keep up Mexico’s assistance to US immigration policy? The transition of power is likely now raising uncertainty in the minds of some Biden officials about what could change with its key partner at the border.