Both the Partido Acción Ciudadana and Casa Presidencial disavowed any knowledge Wednesday of donations from a Brazilian construction firm that was working here.
The Presidency said it rejected categorically the insinuation that tried to relate it to information that linked it to a Brazilian investigation.
The names of both the president, Luis Guillermo Solís, and that of his campaign rival Johnny Araya were found scrawled on documents confiscated by the Brazilian police, a news outlet there reported.
The issue also was raised in the legislature.
Accepting campaign contributions from foreign sources is illegal even though this sometimes takes place. The company in question was OAS, which was supposed to build the San José-San Ramón highway. The deal collapsed after residents demonstrated over the proposed tolls, and then-president Laura Chinchilla canceled the contract and paid off the company.
Acción Ciudadana in a statement said it was loyal to the principles of honesty, transparency and providing its accounts.
The document was in the office of José Aldemario Pinheiro Filho, president of OAS. He is linked with many others to the Petrobras scandal in Brazil.
The document also includes a list of U.S. dollars, but there is no clear link between the money and Solís or Araya.