Karl Rove, President Bush's key political strategist, wins a standing ovation when he promises a Miami audience tougher sanctions on Castro.

BY PETER WALLSTEN AND LESLEY CLARK

With Democrats vowing to exploit a rift between the White House and some Cuban-American leaders, President Bushs top political strategist assured Miami GOP activists Friday night that the administration is committed to economically strangling Fidel Castros government.

In a speech that seemed designed specifically to soothe long-simmering tensions, senior White House strategist Karl Rove devoted more time to Cuba than any other issue -- drawing a standing ovation from the heavily Hispanic crowd at a Miami-Dade Republican Party fundraiser.

''Have no doubt, we will remain committed,'' Rove told the crowd at the Radisson Mart Plaza Hotel and Convention Centre in west Miami-Dade County. Referring to the president, he added: ``He knows, you know, we must not waver.''

PROMISES

Rove unleashed a litany of promises to tighten the grip on Castro, saying the administration would find ''new and creative ways'' to limit the flow of money to the island, punish companies that do business there and crack down on travel.

His strong language comes after months of debate among Miami exile leaders, many of whom have complained that Bush has failed to deliver on campaign promises to crack down on Castro.

Presumptive Democratic presidential nominee John Kerry has said he intends to campaign for Cuban-American votes, while a collection of independent Democratic political committees are planning a massive campaign to point out Bushs failings on Cuba and key domestic issues such as jobs and healthcare aimed at Hispanic voters.

Roves message was a clear indication that the administration is nervous about losing support among Cuban Americans -- especially given the importance of a key voting bloc in the state that decided the 2000 election by just 537 votes.

At the dinner Friday, Rove sat on the dais with some of Miamis most influential Cuban-American leaders: U.S. Reps. Lincoln Diaz-Balart, Mario Diaz-Balart and Ileana Ros-Lehtinen and former state Republican Party Chairman Al Cárdenas.

ENCOURAGED

Rove also sat with state Rep. David Rivera, the Cuban-American lawmaker who along with his legislative colleagues mailed Bush a letter warning that he risked losing Cuban-American votes if he didnt move fast to crack down on Castro.

Rivera said Friday he was encouraged by Roves remarks -- especially his promise that the White House would tighten travel restrictions.

``If they follow through, that would be huge,''

Speaking earlier in the day to Herald editors and reporters, Rove said he was not concerned about the presidents ability to win Cuban-American votes -- especially once they learn about Kerry.

''I think people at the end of the day will look at the record of this administration and look at the alternative, and I know where they'll strongly be,'' Rove said, contrasting a Sunday Herald report detailing Kerrys shifting stances on key Cuba policy issues to what he said was Bushs firm support for stiff sanctions on the island.

''Its an important issue, a moral issue, for this president,'' Rove said.

Rove will join the president in Orlando today for the campaigns first full-scale rally. GOP planners predict the speech will draw 12,000 activists for an event designed to showcase the ''grass-roots'' machine being built in the state.

Speaking to The Herald, Rove said that he had learned lessons from the Florida experience four years ago, when Bush nearly lost the state despite his brother serving as governor and the Republicans apparent dominance in state politics. But he declined to say what those lessons were.

''Lots of things, and I aint going to tell you,'' he said. ``Were working on every one of them.''

The presidents arrival was the focus Friday of what is becoming a daily onslaught of dueling press conferences featuring campaign surrogates from both sides attacking each other.

In Miami, Floridas two Democratic senators, Bob Graham and Bill Nelson, joined U.S. Rep. Kendrick Meek, a Miami Democrat, to assail Bushs record on jobs and healthcare, accuse him of misleading the public on Iraq, and to make the case for replacing Bush.

''Florida wont ever forget what happened in the last election,'' Meek, Kerrys Florida campaign chairman, said, referring to the recount battle that finally awarded the states electoral votes to Bush.

The Democrats remarks drew scorn from Bushs surrogate of the day, Christian Coalition founder and leading GOP strategist Ralph Reed, who said that Nelson and Graham were merely looking to ''audition'' to be Kerrys vice presidential nominee.

WHAT ABOUT JEB BUSH?

During the wide-ranging discussion with The Herald in which he boasted of his intimate knowledge of esoteric matters such as western water wars and agriculture policy, Rove sought to cast aside his reputation as the White Houses all-powerful political puppet master.

Asked about Democrats assertions that he is involved in every major decision from Cuba to Iraq, Rove shot back: ``Im not. My title is senior advisor to the president. Most of the foreign policy things, Im not within 100 miles of. I can tell you more about financing of ag drought relief than you can ever imagine.

And what about the presidents brother, Gov. Jeb Bush? Would be be a formidable presidential candidate in 2008?

''Im focused on 2004,'' Rove said. ``Dont get me in trouble with the governor of Florida.''