2008 Puerto Rico Democratic primary took place on June 1 , 2008 . It was an open primary . Puerto Rico initially planned to hold caucuses , as was done in 2000 and 2004 , on June 7 , 2008 . In December 2007 , an error in the plan was discovered ; the caucus date should have read June 1 , 2008 . Puerto Rico also decided to conduct a primary , rather than caucuses . Puerto Rico sent 55 pledged delegates to the 2008 Democratic National Convention . These delegates were allotted on a proportional basis . The territory 's delegation also included eight unpledged " superdelegates " . Puerto Rico also selected one unpledged add-on delegate . Selection of the unpledged add-on delegate occurred at the Assembly of the Democratic Party of the Commonwealth of Puerto Rico on June 21 , 2008 in San Juan . Polls were open from 8:00 am to 3:00 pm , prevailing local time , Atlantic Standard Time ( AST ) ( UTC-4 , same as Eastern Daylight Time ) . Hillary Clinton won the primary
2008 Democratic National Convention
2008 Democratic National Convention
2008 Puerto Rico Democratic primary