Former President Cristina Fernandez de Kirchner has condemned the government of President Mauricio Macri for manipulating the results of the primary elections on Sunday.
"Yesterday night we saw an unprecedented, extraordinary and embarrassing political manipulation: they tried to hide the truth but won't be able to," Fernandez said in a message shared on Twitter.
Fernandez and her party Citizen Unity have demanded a recount.
The accusations come after Argentina's electoral authority decided to suspend vote counting as Fernandez narrowed in on her rival former Education Minister Esteban Bullrich.
With 95.58 percent of votes in Buenos Aires province counted — home to nearly 40 percent of Argentina's electorate — the ruling party led by Macri's candidate Bullrich had captured 34.19 percent while Fernandez was within a whisker with 34.11 percent.
At this point, the electoral authority stopped counting the votes without including 1,500 voting tables.
Though there has been no official declaration, Fernandez took the stage at a rally around 4:00 a.m. to claim victory as well as criticize the pace of the vote count.
"I never imagined I would have to ask for forgiveness from all Argentines for this embarrassment," she said. "It's an offense to democracy."
Since voting centers closed over 24 hours ago, the complete election results have not yet been released.
Regardless of the final outcome, the candidates will now face each other in the congressional elections in October, when Argentines will elect one-third of the Senate and half the Chamber of Deputies.
However, no matter how many seats Macri's ruling coalition picks up come October, Macri will still lack a majority and must build alliances to pass reforms.
Under Argentina's election system, the winning party in each Senate race gets two of the province's three seats, with the remaining seat going to the second-place finisher.
A second-place finish would thus still grant Fernandez, 64, a Senate seat.
Prior to the election, polls showed Fernandez leading Bullrich, with her campaign for senator for the Citizen Unity gaining mass support.
Fernandez introduced her Citizen Unity political alliance in early July; a movement which aims to form a broad coalition of parties to counter the neoliberalism of Macri’s administration.
Under Macri, economic controls were lifted and social spending slashed, undoing many of the progressive gains made under the Kirchner presidencies of Fernandez and her late husband Nestor Kirchner.