Antiguan Gordon Derrick, president of the Caribbean Football Union which has 25 votes in FIFA's presidential election next month, said there would be no mandate from the body, long a Blatter stronghold, to vote for any one candidate.
While Derrick gave no clue as to where the Caribbean's support may go he said the block vote system, used by former CFU and CONCACAF leader Jack Warner, was a thing of the past.
"Those days are long gone. If there is a democracy and we believe in a democracy then that means that everyone who is nominated has a chance to participate and whoever votes, votes, whichever way," he told Reuters on Wednesday.
The CFU is the largest voting block in CONCACAF, the governing body for North and Central America and the Caribbean which has 35 member associations, a significant chunk of the 209 votes that will decide the next FIFA president.
CONCACAF holds its annual congress in the Bahamas on Thursday and the CFU had its own meeting a day ahead.
Blatter and the three candidates standing against him were all invited as observers to both the CFU and CONCACAF meetings.
Former Portugal international Luis Figo, Dutch FA chief Michael van Praag and Jordan's Prince Ali Bin Al Hussein are hoping to eat into Blatter's support in the region ahead of the May 29 vote.
The United States Soccer Federation, which is the largest federation in CONCACAF, has nominated Prince Ali.
With Warner having quit in 2011 amid the cash for votes scandal, there is a very different landscape for this vote, even if Blatter can still expect plenty of support.
Warner was infamous for enforcing strict discipline on associations to ensure the block vote was kept.
"Because you didn't vote (my way) that doesn't mean you will be victimised, that's not a democracy. Let's not make a farce," Derrick said.
"The Caribbean presidents will get together, casually, they will have read manifestos, discussed issues, we all think alike in a lot of ways so it is quite possible that whoever they decide to go with, it would be a majority of the islands.
"But there will be no mandate," he added.
Apart from Blatter, who made a formal opening statement, the candidates did not address the congress but they will no doubt take advantage of the networking opportunities at the Atlantis resort where the CONCACAF congress is being held.
One delegate, who did not wish to be named, told Reuters that he sensed many of his colleagues were "open" to hearing from all the candidates while another said he was opposed to Blatter and was looking forward to choosing from the alternatives.
Swiss Blatter, 79, has been FIFA president since 1998.