“She’s not the vice president; she’s the co-president,” said Agustín Jarquín, who ran for vice president on Mr. Ortega’s ticket in 2001 but was kicked out of the National Assembly without notice once he fell from favor.  Ms. Murillo, 65, is already a de facto cabinet member, deeply involved in every aspect of the government. She is the one who gives daily news briefings about the latest earthquake or damage from an industrial fire. If a child has Zika, Ms. Murillo knows the boy’s name and might just call the parents herself. She meets regularly with municipal leaders and makes it clear that decisions cannot be made without her approval.  “It’s not that she has as many followers as her husband — she has more,” said Florencia del Carmen López, 48, a street vendor. “The men are annoyed by it. The majority of her followers are women.”  As Ms. Murillo gained more control in the country, the government was widely criticized for taking bolder steps to secure Mr. Ortega’s power, raising troubling questions about the state of Nicaragua’s young democracy.  Nicaragua is a country where a revolution deposed one family dynasty, only to see it at risk of being replaced by another. Mr. Ortega, the president, is a 70-year-old former guerrilla who played a leading role in the Sandinista revolution that toppled Anastasio Somoza Debayle, the dictator whose family ruled here from the 1930s to 1979.  Now the Ortegas and their allies control fuel companies, television stations and public construction projects. At the helm is Ms. Murillo, who has a penchant for hard work that amazes even her opponents. She has made it her business to overhaul everything from the nation’s parks to her husband’s image.  “There were signals: Little by little, her face started showing up as the face on the political propaganda, at first with Daniel and then alone,” said Sergio Ramírez, who was Mr. Ortega’s vice president in the 1980s. “Now it seems she is looking for political legitimacy. This is an extreme search for legitimacy.”  Female heads of state or government are often members of political dynasties. Sometimes they follow their husbands into office, and occasionally their husbands follow them.  Her relationship with Mr. Ortega began in the caldron of war. He spent part of the Sandinista revolution underground in Costa Rica, where he became romantically involved with Ms. Murillo. By then, she already had two children, and she was raising them in a clandestine safe house filled with copy machines, short wave radios and people who assumed false names. Mr. Ortega went by “Enrique.”  Zoilamérica Ortega, Ms. Murillo’s oldest child, was adopted by Mr. Ortega in her late teens. She recalled those early years as chaotic, describing a busy office with people traipsing in and out.  “Nobody took care of us, literally nobody,” she said in an interview.  Ms. Ortega, now 48, publicly accused Mr. Ortega of sexually abusing her for years. She said he had taken advantage of the supervision vacuum of that period and had begun molesting her around the time that the Sandinista revolutionaries claimed victory. She was 11.  She went public with rape accusations in 1998. But her mother, who has had seven children with Mr. Ortega as well, stood by him.  Joined by Mr. Ortega and their adult children, Ms. Murillo held a news conference calling her eldest daughter a liar who suffered from psychological problems.  Although at least one witness backed up the abuse allegations, a legal case against Mr. Ortega collapsed in the courts, which are controlled by the Sandinista party.  Ms. Ortega, the daughter, said she had suffered retribution for going public, contending that the nonprofit organization she ran was routinely cut off from funding sources that feared losing favor with the government. Three years ago, the government deported Ms. Ortega’s Bolivian husband, so she was forced to leave Nicaragua. They now live in neighboring Costa Rica.  “I speak to her only to receive threats,” Ms. Ortega said of her mother. “She opted for an alliance of power.”  Some critics of Ms. Murillo in politics and the news media also contend that her loyalty to Mr. Ortega and her public defense of him were rewarded in the influence she has gained across the country.  Mr. Ortega himself used a Sandinista revolution anniversary speech in July to recount what he told his ally Fidel Castro about Ms. Murillo. Many Nicaraguans took it as a nod to her decision to side with Mr. Ortega over her daughter.  “I was telling Fidel how Rosario’s loyalty dates back to our time in clandestinity,” Mr. Ortega said.  The president said her interest and involvement in politics had been evident early on, when she was arrested for attending a protest and refused to cooperate with the police. After the revolution ended in 1979, the family moved back to Nicaragua, where Mr. Ortega and a committee of eight other men ran the nation.  “The other commanders looked at Rosario as some bothersome person who wanted to get involved,” said Sofía Montenegro, a leading feminist intellectual at the Center for Communication Research, a research group in Managua. “There were nine men, and she did not fit. They had wives who were not interested, and it would not have occurred to them to do so. The men tolerated her.”  But Ms. Murillo, a poet who had attended a British convent school and a Swiss finishing school and was fluent in English and French, wanted a bigger role. Former government officials say she jockeyed to control the Ministry of Culture, where she clashed with high-level administrators and got people fired when they shut her out of decision-making.  Meanwhile, a war raged in Nicaragua as the victorious Sandinista revolutionaries fought insurgents known as the contras, who were backed by the administration of President Ronald Reagan. Mr. Ortega officially became president in 1984 and left office in 1990, when Nicaragua took steps toward peace.  Despite having many children together, the couple did not marry until 2005, just as they prepared to take another shot at the presidency. Mr. Ortega had lost three consecutive elections. Then, with Ms. Murillo’s help, he won in 2006, and her influence was notable right away. She is credited for the government’s bold efforts to help the poor by doling out new houses, pigs and tin roofs.  But she also clashed with members of her husband’s longtime inner circle, sidelining them one by one and kicking them out of their offices in the presidential palace. The National Assembly and the courts were stacked with allies. The law was changed so that Mr. Ortega could run indefinitely.  In June, the Supreme Court banished a leading opposition figure from his own party, the Liberal Independent Party, preventing him from becoming an opponent in the November election. In August, more than two dozen opposition members were expelled from the National Assembly after they refused to recognize the person the government had selected to lead their party.  Now some Nicaraguans are worried that even more power will be consolidated in the Ortega family.  “She wants to continue having power — that’s a sickness,” said Sergio González Gutiérrez, 42, a taxi driver, who gathered with his family at a corner store in San José Oriental, Ms. Murillo’s old neighborhood. “If a private company does not allow a married couple to work together, how is that allowed for a nation?”  The government contends that the Nicaraguan Constitution prohibits only blood relatives — like two siblings, or a parent and a child — from being on the same ticket. But many political analysts say the couple is violating the part that also excludes people who are related “by affinity.”  Dozens of people interviewed for this article, from former government officials to people on the street, said they believed that the plan to put Ms. Murillo in office was intended to guarantee the family succession.  “I met her when she was 17 years old and the secretary for the publisher of the newspaper, and I was always impressed with her ability to work, which people still notice,” said Ángela Saballos, the spokeswoman for the Nicaraguan Embassy in Washington during Mr. Ortega’s first term in office. “She must sleep three hours.”  Her pursuit of the vice presidency, Ms. Saballos said, appears to be an attempt to “legalize all the work she has been doing.”  Ms. Murillo is already the official government spokeswoman, so no other bureaucrat is authorized to speak to the news media except her. In an email, she declined to be interviewed. (She speaks mostly to news organizations that are controlled by the government, several of them by her children.)  “This is a movie we already saw, and we know how it ends,” said Mr. Ramírez, the former vice president. “It ends badly.”  A version of this article appears in print on October 31, 2016, on page A1 of the New York edition with the headline: Wife. Then First Lady. And Now Running Mate. Order Reprints| Today's Paper|Subscribe
Rosario Murillo, President Daniel Ortega’s wife, has risen by winning over the poor and the public, but also by pushing out many in Mr. Ortega’s inner circle.