US Republican presidential candidate John McCain, accompanied by his wife Cindy, arrives in Mexico City

US Republican presidential hopeful John McCain arrived in Mexico Wednesday on the second stop of his short Latin America tour seeking to score points with the large Latino voting block back home.

With his previous stop in Colombia overshadowed by the dramatic rescue of 15 hostages of the leftist FARC guerillas, and amid talk of a shakeup in his campaign organization, McCain flew into the Mexican capital planning to meet President Filipe Calderon on Thursday.

McCain was expected to express his support for Calderon's battle against narcotics gangs and organized crime during the 24-hour stopover, in the wake of the US approval last week of the 1.6-billion-dollar, three-year package of anti-drug assistance to Mexico, Central America and the Caribbean known as the Merida Initiative.

"Drug cartels have basically taken control of some towns on the Mexican border," McCain told ABC News Wednesday, speaking from the Colombian seaside city of Cartagena.

"There is clearly a continued threat of drugs pouring into the United States of America, which can harm us and our young people very badly."