MSCI's index tracking the region's equities .MILA00000PUS rose 0.95%, while its currency equivalent .MILA00000CUS also gained 0.8%.
In Brazil, a BTG Pactual/Nexus poll showed on Monday that President Luiz Inacio Lula da Silva and right wing Senator Flavio Bolsonaro remain tied, with the leftist incumbent holding a narrow lead within the survey's margin of error.
The real BRL= edged 0.64% higher, while the Brazilian benchmark index .BVSP rose 0.61%.
Though the sentiment for the region's equities have improved in September, investor remain cautious about adding to their position ahead of the elections. A Latin America fund manager survey by Bank of America Global Research showed that while more than 70% of participants see the benchmark at 180,000 points or more than that, only one-third of participants said that they would be willing to add to equities at current levels.
"The next president will choose the direction of economic policy, but Congress and fiscal arithmetic will determine how far that agenda can travel," said BofA Global Research economists in a note.
Brazil's September mid-month inflation figures are expected later in the week. The central bank of Brazil delivered a 25 basis points rate cut last week, with private-sector economists polled weekly by the bank expecting additional quarter point rate cut at the end of 2026.