A judge investigating the scandal said it appeared that government officials bribed senators of the opposition Peronist party, as well as some of its own senators, to vote for a controversial labour reform bill earlier this year.
Three senators have already surrendered their immunity from prosecution and four others have offered to resign their seats after the judge formally asked the Senate to strip eight legislators of their protection in connection with the alleged bribes.
Nevertheless, Vice-President Carlos Alvarez said he would not rest until the pay-off allegations had been fully clarified, according to a report in the Buenos Aires Economico.
Presidential fears
Deputising for President De la Rua - attending a South American summit in Brazil - Mr Alvarez pledged to push ahead with the judicial investigation "regardless of who comes to grief and whatever the cost may be."
Mr Alvarez said he had been told by Mr De la Rua: "The country must not be brought to a grinding halt" by the scandal.
The daily La Nacion quoted the president as saying that any government official found guilty of paying the bribes would "immediately be removed from office."
"Severe crisis"
Not surprisingly, the press has been having a field day with the case. La Nacion said the purchasing of Senate votes was said by some to be part of the parliamentary culture.
But this latest scandal was a "severe crisis which threatens to destabilise the institutions of Argentine democracy," La Nacion warned.
It rejected proposals to declare any sort of emergency measures which compromised the democratic system, recalling the periods of military or authoritarian rule.
"Argentina has paid a high price in the past - and continues paying it - for having interfered with the law-based state," said the paper.
Painful episode
"Nothing justifies altering the current judicial system, however deep the moral or political problems confronting society."
The paper was confident that "Argentinians would emerge from this painful episode with hope, with the awareness that the only way to cure the shortcomings of the democratic system is with more democracy".
Another leading daily, Clarin, called for major revisions to the legislative process, warning that getting rid of a number of senators would not be enough.
It called for both the government and opposition, as well as the judiciary, to act "rapidly and transparently" to avoid a "crisis of confidence" in the democratic system.
"It must not be forgotten that the [governing] Alliance based its electoral campaign on the defence of transparency and the fight against corruption," the paper points out.
"The undermining of the Senate will only serve to discredit the laws and norms regulating the life of the republic."
Could get worse
"Where will it end?", the English-language Buenos Aires Herald asked. "The Senate scandal has snowballed spectacularly in the last fortnight but there is still plenty of scope for escalation."
Both major parties insisted that President De la Rua was above suspicion, the paper said, "even if the intention sometimes seems to be to start people thinking the precise opposite".
The daily warned that the crisis could spill over into "every corner" of the executive and legislature, affecting the handling of an "ailing economy in need of urgent action".
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