This month marks the 35th anniversary of the Sandinistas' ouster of dictator Anastasio Somoza, and as always on such occasions, Murillo stood beside Ortega at the official commemoration, welcoming Latin American dignitaries with a bejeweled fist raised in triumph.
"The faith in each and every one of us has made it possible for God to fill us with miracles," Murillo told the crowd.
"Who would have said that 35 years would pass so quickly, always in the scent and roar of combat," she went on. "The revolutionary people of centuries past and present inspire us in the advance of socialism that, for us in Nicaragua, is made up of Christian faith, family values, the life and spirit of community."
Politics long have been a family affair in Nicaragua, and Latin America has a tradition of women leaders stepping in when their husbands leave the political stage. Given that, the political partnership of Ortega and Murillo leads many here to speculate that she aspires to succeed Ortega as president one day.
Ortega may have fueled a recent spate of such talk in April after a magnitude 6.2 earthquake damaged many buildings in the capital of Managua. He went on television to say that while he protected their grandchildren, Murillo began issuing instructions to Cabinet members.
"The problem with the presidential couple is that their vocation is to remain in power," said Rosa Maria Zelaya, former president of the council overseeing elections. "They are preparing the succession in the person of Murillo, for whenever it is necessary."
Barring illness or death, the 67-year-old Ortega is not likely to leave office soon, thanks to his backers in Congress and on the Supreme Court who approved a constitutional change allowing for unlimited re-election. And supporters say the image of a power-hungry first lady is a form of sexism that overlooks her many contributions to Nicaragua.
"The opposition would love for Murillo not to exist," said Aldo Diaz Lacayo, former Nicaraguan ambassador to the United Nations. "She is efficient, productive and pivotal in implementing all of the government policies."
Murillo, 63, joined the Sandinista movement in the 1960s, while working as a secretary to La Prensa newspaper editor Pedro Joaquin Chamorro, who was later assassinated for his opposition to the Somoza regime.
In a photograph taken July 19, 1979, the day Somoza fled Nicaragua, Murillo is wearing green fatigues, a black beret over short hair, and a rifle slung over her shoulder, standing with several of the nine Sandinista commandants who led the uprising.
Today, Murillo's shoulders are draped in her jet black hair and colorful outfits, many of them pink and blue, apparently for the New Age colors of divine purpose and harmony with family and the world. Besides references to God, Murillo's speeches are peppered with allusions to the mysteries and miracles of life, and Mother Earth.
Many Nicaraguans see her as their protector.
"We are the children and she is the mother who takes care of us," said Dennis Centeno, a computer programmer who was attending a concert in commemoration of the Sandinistas' namesake, Augusto Cesar Sandino.
A lover of jewelry, Murillo wears multiple necklaces and bracelets and several turquoise rings on each finger. Her style provides a vibrant contrast to Ortega, who has grown bald and paunchy with age, and usually dresses in a plain white shirt.
While all but one of the original Sandinista leaders have either split with Ortega or died, Murillo remains his confidant, gatekeeper and spokeswoman. Supporters and detractors alike say that to get to Ortega, they first must go through Murillo.
"Ortega holds the political power, but she wields it in his name," said Dora Maria Tellez, the Sandinista militant who led an assault on the National Palace in 1978, taking Somoza's congress hostage.
Tellez broke with Ortega and Murillo years ago over their authoritarian style of governance, she said. "Before it was Somocismo, now it's Orteguismo. The Somocista political model has not been defeated in Nicaragua."
Ortega ruled Nicaragua from 1979 to 1990, first as coordinator of the Junta of National Reconstruction and then as president, until losing an election to Violeta Chamorro, the wife of the assassinated newspaper editor for whom Murillo had worked.
Murillo led the re-election campaign that returned Ortega to power in 2006, and another in 2011. The Ortega government identifies with left-leaning leaders of Latin America such as Cuba's Raul Castro and Venezuela's Nicolas Maduro, and calls itself socialist for the handouts it gives to the poor.
Thanks to about $500 million a year in support from Venezuela, thousands of Nicaraguan families receive sacks of beans, rice and other basic foods each month, plus dried fruit and sardines for Christmas and Mother's Day. And there are free doctor's visits for the poor.
In the eyes of ice cream vendor Leonel Lopez, that's good government. His children also receive school supplies and free school lunches.
"They help us because we are poor," said Lopez.
But the government's mainstay is the business community it once opposed. Jose Adnan Aguerri, president of the Nicaraguan Council of Private Enterprise, said that his organization has supported an overwhelming majority of the laws passed by the Sandinista-controlled congress. They generally hammer out their differences with Ortega and Murillo before a law is submitted to a vote.
"We're not going to beat the Sandinistas in elections. We have to make deals," Aguerri said.
The government's biggest business deal isn't with local entrepreneurs. The concession to build the Great Inter-Oceanic Canal of Nicaragua, a waterway three-times the size of the Panama Canal, has been granted to Beijing-based telecommunications CEO Wang Jing, along with tax-free side projects including ports on Nicaragua's Pacific and Atlantic coasts, an oil pipeline bisecting the country, a cargo railway, two free-trade zones and an international airport.
The proposed canal is not without detractors. Some question why the government has not been forthcoming about funding sources, timelines or regulations to control the sizable construction project.
But Ortega and Murillo hail it as the beginning of a new and prosperous future for Nicaragua. The government is to be paid $10 million a year for 10 years once the canal is built, and gradually will secure full ownership of the waterway in a century.
When the proposed route of the canal was announced this month, Murillo called it "almost a reality" and thanked God.
"We are in the month of July, the month of transformations, month of our evolution," Murillo said. "Comrades, it is a historic day for our country, a day of great transcendence in the ... material, social, cultural transformation of the life of our country."
In the 1980s, Murillo was the leader of the Culture Workers Union and in the '90s she was a member of congress and spokeswoman for the Sandinista Front, then an opposition party.
For many former allies, the break with Murillo came in 1998 when her then-30-year-old daughter, Zoilamerica Ortega Murillo, publicly accused stepfather Daniel Ortega of having repeatedly sexually abused her as a girl. She filed charges against her stepfather but later dropped them and moved to Costa Rica. She declined an interview request for this story. Ortega denied the charges and Murillo publicly defended him.
"Ortega kept quiet, paralyzed, and she (Murillo) took on the strategic defense," said Azalia Solis, a feminist activist and former Sandinista guerrilla. "She delivered her own daughter and charged a price: power."
Since then, Ortega and Murillo have kept the rest of their large family close. Most of their extended family lives in a compound in central Managua surrounded by high walls, and they travel in convoys with heavy security. The government, Ortega family and friends control most of the media, including seven of the country's eight television stations and the newspapers, except for the Chamorro family's La Prensa.
Murillo is a communications chief who takes no hard questions and doesn't suffer critics. Government officials meet only with the most trusted Sandinista journalists. Even those loyal to Murillo decline to discuss her achievements on the record, for fear of a reprimand. Repeated requests for interviews with Murillo, four government ministers, the mayor of Managua and Sandinista Front officials went unanswered.
"Ortega and Murillo have been a political duo for years," said Carlos Fernando Chamorro, editor of the online publication Confidencial.
Chamorro is the son of former President Chamorro and her late husband. Once a Sandinista, he now is a strong opponent of the Ortega-Murillo team. He and his online publication have been the target of government political attacks, including criminal investigations for alleged money laundering that date back to 2008 and remain open.
"He makes the decisions and she delivers the government's message ... appealing to the most conservative values of Nicaraguan society," Chamorro said. "There are two values: the traditional family and the word of God interpreted by the will of his representative in Nicaragua, in terms of communication, which is Rosario Murillo."