Fernandez, 60, was defiant as she attended public meetings after defeats in primaries and amid preparations for mid-term elections.
Critics say the president, re-elected with an overwhelming majority in 2011, is losing support because of controversies over her policies, mounting economic problems and muzzling of dissent. In particular Fernandez is accused of using the state's tax apparatus to intimidate and suppress independent media.
Her government's alleged doctoring of economic and financial data has reached epic proportions, critics say, and angered both the International Monetary Fund and the World Bank. EU negotiators seeking trade deals with Buenos Aires also questioned government figures on Argentina's economic performance.
U.S. President Barack Obama withdrew trade privileges for Argentina after her administration was found to be delaying settlement of multibillion-dollar creditor claims dating back to the country's $95 billion sovereign default in 2001.
Last month IMF Managing Director Christine Lagarde withdrew a proposal to back Argentina in the country's legal battle over its defaulted debt, citing U.S. opposition.
"The managing director's recommendation was premised on U.S. support, as it would not be appropriate for the IMF to file this brief without that support," the IMF said.
Critics accuse Fernandez of mishandling Argentina's position and of antagonizing friends and foes alike in Argentina and abroad.
The Oct. 27 mid-term elections will decide the future make-up of Argentine Parliament and since Sunday's primaries, Fernandez has been defiant.
She accused the media of misinterpreting electoral results, denounced Tigre Mayor Sergio Massa, a major winner, and exhorted loyalists to do more to propagate the government's socially inclusive economic reform programs. Results of government policies are challenged by opposition critics and media analysts.
"Some talk about the future, I tell them the future is here, with all these youngsters. If this isn't the future, where is it?" she asked. In contrast, she said of the opposition: "They are the past. They are not new. They are well and badly remembered by everybody."
Massa, 41, is seen as a future presidential candidate and his win in the affluent Buenos Aires electoral district is being hailed as a sign of an emerging new leadership with Fernandez the main focus of that challenge.
Farmers' associations and trade union leaders say presidential policies have brought hardship and ignored sectors that are major foreign exchange earners.
Fernandez aides say the country is still recovering from the 2008 financial crisis and cite government plans to redesign economic recovery with policies that achieve "growth with social inclusion."
Critics say the government's poverty reduction programs have passed by the country's long impoverished communities.
"Argentina is a relatively rich country. Yet despite this wealth, it is also a country with a relatively high level of poverty," a World Bank report says.
The poverty rate in Argentina dropped to 5.4 percent last year and indigence was down to 1.5 percent, the government statistic office said in a report dismissed by critics as controversial and unreliable.