Billionaire Carlos Slim has had harsh words for Mexico’s presidential frontrunner, saying recently he is “concerned and afraid” about what leftist Andres Manuel Lopez Obrador might do if elected.

But a victory by Lopez Obrador, who holds a double-digit lead in most polls before the July 1 vote, could provide upside for Slim’s fortunes, particularly with regard to his America Movil (AMXL.MX) telecommunications empire, Reuters interviews with a dozen close friends, partners and other people familiar with their dealings show.

Lopez Obrador’s pick for telecoms minister, Javier Jimenez, told Reuters he favors re-examining some regulations stemming from Mexico’s landmark 2014 telecommunications reform, a law that has clipped America Movil’s profits and inhibited its expansion.