BUENOS AIRES, Argentina (AP) -- President Cristina Fernandez failed the first electoral test of her second term Sunday as her party's candidates trailed opponents across Argentina's most populous provinces in congressional primaries. If the voting pattern repeated in October's elections, she could lose control of congress during the final two years of her rule.
The governing party remains the only political force in Argentina with a nationwide organization, but her opponents are coming up strong, especially in the all-important province of Buenos Aires.
With 52 percent of the vote counted in the suburbs around Argentina's capital, Sergio Massa's Renewal Front was leading the president's hand-picked candidate, Martin Insaurralde, by 34 percent to 29 percent.
The governing Front for Victory party got the most votes in six of seven provinces with senate races, but its slates for the house of deputies led in only eight of Argentina's 23 provinces and trailed in all of the most populous provinces as well as the city of Buenos Aires.
Massa, who broke from Fernandez only 40 days before the primaries, sounded more like a presidential candidate than a campaigner for congress in his victory speech. He invited people from across Argentina's polarized political landscape to join him in a new movement that would rule from the center, build coalitions and protect the middle class, a group he said had been neglected by Fernandez.
"We have to think of the future. We have to learn to stop looking at the past as a way to build a future for all Argentines," Massa said. "We feel proud that the path we have chosen is one of unity in diversity, of coming together without aggression ... the people who have joined us are saying 'enough with confrontation in Argentina."
Fernandez won re-election nearly two years ago with 54 percent of the vote, but her popularity has dropped since then amid corruption scandals involving her appointees and close allies, growing discontent over inflation, deteriorating public services and what many see as a weakening of the nation's institutions in the face of authoritarian presidential power.
The president took the stage with Insaurralde and other governing party candidates and then did all the talking at a post-election rally, refusing to concede any defeat and warning Argentines not to trust politicians who make promises they can't keep.
"There may be other politicians showing up offering something different," Fernandez said. "I ask that all of you think about what we've done in the last 10 years."
"My great responsibility as president is to provide governability to Argentina," she added. "Don't expect me to promise things we can't provide. Because we have to rule in a complex world. That's not to say we're the most intelligent or the best, by God, we're human; we make mistakes. But we don't promise what we can't provide."
The vote was Argentina's first obligatory nationwide primary, but most parties settled on "pre-candidates" beforehand and presented unified slates, turning the election into a party-popularity contest.
With half the seats in congress and a third of seats in the senate up for grabs Oct. 27, the results could determine whether Fernandez will have new checks on her power. Currently, she doesn't need the votes of any opposition lawmakers to provide the quorums she needs to push through legislation or quash investigations.
If her opponents firmly control at least a third of the seats, they could end any chance of changing the constitution to eliminate the two-term limit on presidencies. Whoever wins big in October also could become a leading candidate to succeed her in 2015.
The government's opponents led Sunday in house races in 13 provinces including Argentina's biggest population centers -- Cordoba, Santa Fe, Mendoza, Santa Cruz and the capital of Buenos Aires, where the ruling party slate came in third, with 19 percent.
Even more important was suburban Buenos Aires, the president's traditional stronghold, where 35 percent of the country's voters live, and where Massa and Insaurralde have carried on a proxy battle between Fernandez and her opponents.
Insaurralde, a 43-year-old mayor of Lomas de Zamora, was hand-picked by Fernandez and showered with attention as she sought to improve his name recognition. She even brought him to Rio de Janeiro for a photo-opportunity with Pope Francis.
Massa, the 41-year-old mayor of the wealthy riverfront Tigre municipality, briefly served as Fernandez's Cabinet chief and now leads a breakaway branch of Peronism, the broad and splintered political movement that many Argentines claim some allegiance to.
This was also the first election to include 16- and 17-year-olds, a new block of more than a half million voters that Fernandez in particular has courted. In all, more than 70 percent of 30 million registered voters cast ballots.
Associated Press writer Debora Rey contributed to this report.
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