PORT-AU-PRINCE — The U.S. State Department said Friday it revoked the visas of about a dozen Haitian officials, increasing pressure on the government to drop its favored candidate from the presidential runoff in favor of a popular contender who is warning of renewed protests if he is not on the ballot. Revoking visas that let prominent Haitians enter the United States is the latest step in an escalating effort to persuade Haiti's government to accept international monitors' finding that Michel Martelly rightfully belongs on the second-round ballot Martelly has adopted a combative stance and urged his supporters to take to the streets peacefully if the electoral council does not allow him to run against top vote-getter Mirlande Manigat in the runoff, in place of Jude Celestin. Demonstrations in December shut down all Haiti's major cities for days, hampering earthquake reconstruction and efforts to halt a cholera outbreak that has killed nearly 4,000 people. ``We are ready to fight for justice for everyone,'' Martelly said at a news conference while surrounded by bodyguards. ``We won't accept an electoral coup.'' Preliminary official results from the first round of voting showed Martelly failing to reach the runoff — finishing just behind Celestin, President Rene Preval's chosen successor. But an international team of experts from the Organization of American States found problems with the count. Its calculation indicated Martelly, a singer known as ``Sweet Micky,'' beat Celestin and should be in the runoff. The U.S. and other foreign forces have been pushing the government to accept that ruling. A senior State Department official, speaking on condition of anonymity because of privacy concerns, would not specify the names of the officials whose visas were revoked or state the specific reason for the action. But State Department spokesman P.J. Crowley stressed to reporters that the U.S. wants to see the Haitian government accept the OAS recommendations. ``To the extent that there are individuals who are connected with episodes of violence or corruption, you know, we will not hesitate to take appropriate action,'' he said. Haiti has been in a political crisis since the announcement of results from the Nov. 28 election, which featured documented cases of fraud and widespread disorganization. The second round was originally scheduled for Jan. 16 but postponed amid the wrangling. Critics including the left-leaning Washington think tank Center for Economic and Policy Research have argued that the entire election was flawed and should be thrown out and done over. If the Haitian government accepts the OAS recommendation, Martelly, a populist who says he will be more active than Preval and advocates re-establishing Haiti's banned military, would be a strong challenger to Manigat, a former first lady and law professor who is a more muted conservative and finished comfortably in first place. Though he accepted the OAS team's presence during the election, Preval is reportedly unhappy with its recommendations and incensed that its report was leaked to the press before he had officially received it. He has not commented publicly. The provisional electoral council, appointed by Preval, played down the OAS recommendations, saying it would consider them as one appeal among others filed by candidates and observers. But on Thursday, the U.S. Ambassador to the United Nations, Susan Rice, made it clear that Washington wants the report implemented. ``Sustained support from the international community, including the United States, requires a credible process that represents the will of the Haitian people,'' Rice said. Washington is waiting to release nearly $1 billion in promised post-earthquake reconstruction aid to Haiti. Billions more have been promised by other nations. Martelly read Rice's comments as a threat of possible sanctions similar to a crippling embargo against the military junta that ruled Haiti in the early 1990s. ``How can Haiti afford an embargo right now?'' he said. Haitian radio also reported Friday that the U.S. tourist visas of several officials close to Preval had been suspended. The U.S. Embassy declined to comment, citing privacy rules for individual visa decisions. U.N. peacekeeping chief Alain Le Roy also warned that Haiti could face more political instability unless the government accepts the OAS recommendations. Following the Dec. 7 announcement of the election results, pro-Martelly demonstrators paralyzed cities across Haiti for days. The United States renewed its travel warning for Haiti on Thursday, citing in part the recent demonstrations. ``We are going to take to the streets peacefully,'' Martelly said Friday. ``I am in a fight to make sure the voice of the people is respected.'' Associated Press writer Desmond Butler in Washington contributed to this report.