- Josefina Vásquez Mota of the National Action Party (PAN). PAN is currently in power with President Felipe Calderón.
- Enrique Peña Nieto of the Institutional Revolutionary Party (PRI). PRI was in power under various names from 1928 to 2000.
- Andrés Manuel López Obrador of the Party of the Democratic Revolution (PRD). López Obrador also ran in highly controversial election in 2006 and according to the Federal Electoral Institute lost by 0.56 percentage points to Felipe Calderón, resulting in mass protests).
- Gabriel Quadri de la Torre of the New Alliance Party (PNA or PANAL), which was created in 2005.
I find it interesting that other parties have candidates for Chamber of Deputies or the Senate, but not for President and therefore form alliances with the three main parties (PAN, PRI, and PRD). For example, López Obrador is a candidate for PRD, the Labor Party and the Citizen's Movement. Enrique Peña Nieto is a candidate for PRI and Ecologist Green Party of Mexico.
Because of Mexico's Article 33 in the Constitution (which basically says foreigners can't get involved in any way in politics or can be kicked out), I'll keep my opinions to a minimum here and just say that I'm not quite a fan of some of the candidates. We'll see what happens July 1st.