BY SUSAN ANASAGASTI AKUS AND FRANCES ROBLES

Aníbal Acevedo Vilá became Puerto Rico's first governor in history to face federal charges Thursday, when the U.S. Attorney here unsealed a 27-count indictment accusing him and a dozen others of a scam to exceed campaign finance limits. Acevedo quickly shot back, saying the federal prosecutors are ``looking for blood.''

Calling the investigation a ''multimillion-dollar political witch hunt,'' he denied wrongdoing and vowed to hang on to his post. He is seven months from an election in which he is seeking a second term.

The 46-year-old governor and his supporters claimed the Department of Justice under President Bush has a penchant for going after Democrats. And they say the Popular Democratic Party governor was targeted because he sued the federal government in 2005 over its handling of the FBI's killing of an independence activist and fugitive.

The 19 charges boil down to whether the governor dipped into campaign funds for personal use and engaged in an elaborate scam to use straw campaign donations designed to skirt spending limits. Convictions could mean 20 years in prison.

''This is not a just, balanced and honest investigation,'' Acevedo said at an afternoon press conference. ``They are lies and falsehoods.''

Acevedo is expected to turn himself in Friday to face charges that he essentially laundered illegal campaign contributions through a public relations company, which provided fake invoices to make the donations look like legitimate payments for services.

The longtime politician is viewed as a controversial figure and tough leader who served as the island's Washington representative for four years. He supports Puerto Rico's commonwealth status and was the first governor to enact a sales tax.

The fraud scheme he is now accused of was designed -- according to the U.S. Attorney's Office -- so the campaign could hide donations and accept $7 million in public financing which required that he keep spending down. An ad agency allegedly filtered up to $800,000 in donations.

Democratic Party operatives in Philadelphia, who were also charged, raised tens of thousands of dollars in the names of friends, relatives and employees who were reimbursed in cash. The governor allegedly used his power to intervene on behalf of the Philadelphia fund raisers who sought government contracts for their consulting clients.

Robert M. Feldman, a Pennsylvania political consultant who has raised $1 million for Democrats, was charged with a single count of conspiracy.

The indictment also alleges that Acevedo used campaign funds to pay personal American Express bills and go on trips with his family. The tab: $15,000 for trips to Miami, Orlando and Costa Rica, including airfare for his two kids to go to China.

''The darkest moment in the life of a man is when he sits down to plan how to spend money he did not earn,'' said Luis Fraticelli, special agent in charge of the FBI San Juan office. ``It's very sad when a governor or any other public official is charged with serious federal crimes.''

Acevedo was charged with conspiracy to violate election laws, making false statements, wire fraud, fraudulently obtaining federal funds, conspiracy to defraud the IRS and filing a false tax return. Members of his campaign staff, his administrative aide, his legal advisor, prominent Puerto Rican businessmen as well four people in Philadelphia were also indicted.

For Puerto Rican Democrats, the case exemplifies politically motivated investigations like the ones that eventually brought down U.S. Attorney Alberto Gonzales, who was accused of selective prosecutions and promotions based on party affiliation.

Acevedo also has long accused the FBI of seeking revenge against him for his lawsuit over the September 2005 killing of fugitive Filiberto Ojeda Ríos in a standoff with the FBI.

But Fraticelli stressed that word of Acevedo's alleged campaign scheme first emerged in 2004, and the investigation opened in June 2005, three months before Ojeda was shot.

Acevedo got payback of his own: the nomination of interim U.S. Attorney Rosa Emilia Rodríguez, who took Acevedo's case before a federal grand jury, was stalled indefinitely.

''They care little about the truth, justice or what's right,'' Acevedo said of prosecutors. ``They want political advantage.''

Late last year, the governor's lawyer asked the Justice Department to remove Rodríguez from the case and assign it instead to Justice Department lawyers in Washington. Acevedo's supporters say she is too close to Luis Fortuño, Puerto Rico's representative in Washington and Acevedo's opponent in the November election.

''My client's principal complaint,'' attorney Thomas C. Green wrote in a brief submitted to the Justice Department, ``is that virtually every facet of his life as an elected official has been subjected to scrutiny in the course of an apparently unending investigation that appears not to be about specific allegations of misconduct but rather a determined effort to find something, anything, that can be used to prosecute the governor and ruin him politically on the eve of an election.''

Prosecutors denied politics played a role.

''We are not politicians, we have said it several times,'' Rodríguez said Thursday. ``Our job is to make sure federal law is followed.''

Fraticelli said the three lead FBI agents assigned to the case have no affiliation with any of the political parties in Puerto Rico and the case was subject to much scrutiny from his Washington supervisors.

In a statement Thursday, Green reiterated: ``It is particularly disconcerting that this indictment comes after three years of investigation, two grand juries and in the middle of an election year, in fact, only months before the election. This is an unprecedented and undeserved intrusion by the federal government into the affairs and electoral process in the Commonwealth.''

``I assure you that these charges against the governor will be vigorously contested and exposed as senseless.''

McClatchy Washington correspondents Marisa Taylor and Greg Gordon contributed to this report.