MIAMI - A new study says supporters of tough U.S. sanctions against the Cuban government have given more than $10 million to congressional campaigns over the last seven years.

The nonprofit Public Campaign, which supports campaign finance reform, says the study shows how large sums of money from a small group can influence lawmakers.

Public Campaign cites a number of times in which lawmakers changed their position on Cuba-related issues within months of receiving funds from a political action committee that supports the U.S. embargo of the communist island.

Those who back the PAC say they're being unfairly targeted for their passionate views toward their homeland. They note many other groups channel money to politicians who support their views.

Like many other interest groups, those who support the U.S. embargo of Cuba have long donated heavily to whichever party is in power and spread the funds among legislators across the country.