Anti-corruption watchdogs wonder: 'Who is funding Mexico's presidential candidates?'

FILE PHOTO: A combination picture shows candidates (L to R) Leftist front-runner Andres Manuel Lopez Obrador of the National Regeneration Movement (MORENA), Institutional Revolutionary Party (PRI) presidential candidate Jose Antonio Meade and Ricardo Anaya, presidential candidate for the National Action Party (PAN), leading a left-right coalition, addressing the audience during a conference organised by the Mexican Construction Industry Association in Guadalajara, Mexico, March 23, 2018. REUTERS/Henry Romero/File Photo

MEXICO CITY (Reuters) - Mexico's three leading presidential candidates have not declared a single peso in direct private financial contributions to their election campaigns, federal records show, raising concerns from corruption watchdogs about the potential influence of dark money in a pivotal contest.

Candidates from Mexico's three main political parties said they have relied almost exclusively on money from their parties, which is overwhelmingly public, to bankroll their campaigns, a total of more than 634 million pesos (24.5 million pounds).