This bit from the Wikipedia article on the topic is actually quite interesting:
> In June 2000, a US Congressional Black Caucus (CBC) delegation visited Cuba to meet with Castro. Representative Bennie Thompson (D-Miss.) mentioned to Castro that his district had a shortage of doctors; he responded by offering full scholarships for US nationals from Mississippi at ELAM. Later that same June, in a Washington, D.C. meeting with the CBC, the Cuban Minister of Public Health expanded the offer to all districts represented by the CBC. At a September 2000 speech event at Riverside Church, New York City, Castro publicly announced a further expanded offer which was reported as allowing several hundred places at ELAM for medical students from low-income communities from any part of the USA. Reports of the size of this offer varied in the US press: 250 or 500 places were suggested with perhaps half reserved for African-Americans and half for Hispanics and Native Americans. The ELAM offer to US students was classified as a "cultural exchange" program by the US State Department to avoid the restrictions of the U.S. embargo against Cuba. The first intake of US students into ELAM occurred in spring 2001, with 10 enrolling in the pre-medical program.[5][18][20][21]
> In 2004, the legality of the presence of US students at ELAM was threatened by tightened restrictions against travel to Cuba by US nationals under the administration of President George W. Bush. A CBC campaign led by Representatives Barbara Lee (D-Calif.) and Charles Rangel (D-NY) with 27 other members of Congress persuaded Secretary of State Colin Powell to exempt ELAM from the tightened restrictions.[4]
> Applications from US citizens had been administered through the New York City-based Interreligious Foundation for Community Organization (IFCO), headed by human rights activist and critic of the U.S. embargo of Cuba, the Rev. Lucius Walker Jr.[21]