The Illinois senator leapt into the long-running and often bruising debate over U.S.-Cuba policy with an op-ed piece published in The Miami Herald.

"The primary means we have of encouraging positive change in Cuba today is to help the Cuban people become less dependent on the Castro regime in fundamental ways," Obama wrote.

"Unfortunately, the Bush administration has made grand gestures to that end while strategically blundering when it comes to actually advancing the cause of freedom and democracy in Cuba," he added.

He said that was true of the travel and money restrictions imposed in 2004, adding that the move isolated those on the island from "the transformative message carried there by Cuban Americans." He promised to grant Cuban exiles unrestricted rights to visit their families and to send remittances home.

While the U.S. embargo has limited who can travel to the communist island and what can be sent there since the early 1960s, Bush's restrictions made visiting and shipping gifts to Cuba more difficult.

Now most Cuban-Americans can only visit the island once every three years and can only send quarterly remittances of up to $300 per household to immediate family members. Previously, they could visit once a year and send up to $3,000. The U.S. also tightened restrictions on travel for educational and religious groups.

The Cuban-exile vote is considered key to winning Florida, and top presidential candidates have generally followed the recommendations of the community's most hard-line and vocal leaders, who support a full embargo against Fidel Castro's government. Castro, 80, is in poor health and turned over temporary power last year to his brother Raul.

But sentiment in the Cuban-American community is changing. Unlike the early waves of immigrants who brought their entire family, often by plane, to the U.S., most Cubans now flee by boat and are forced to leave relatives behind. Fewer of these immigrants were overt political opponents of the government, and they want to be able to visit loved ones and to send money home.

Many Cuban exiles are also frustrated with the U.S. embargo, which has failed to yield fruit after nearly 45 years. And with the specter of an ailing Castro and a possible change in leadership, they are more open to changing U.S. policy.

No other current top presidential candidate has sought to ease the restrictions.