TALLAHASSEE — The U.S. Department of Justice is keeping a watchful eye on Florida for possible voting rights abuses in the last days of a close, hard-fought battle between Gov. Rick Scott and Charlie Crist.

Tampa Bay's top federal prosecutor on Wednesday urged voters to report suspected cases of fraud or voting rights abuses.

U.S. Attorney A. Lee Bentley III said he has designated Assistant U.S. Attorney Bob Mosakowski to be a district election officer, chiefly responsible for investigating complaints. Mosakowski can be reached at (813) 274-6129. The Voting Section of the Justice Department's Civil Rights Division can be reached toll-free at 1-800-253-3931.

Bentley said FBI agents across the United States will investigate any voting-related complaints. He said it's a crime for anyone to intimidate a voter, to mark a ballot against a voter's wishes or to question or photograph voters at polling places under the pretext of uncovering violations of voting rights laws.

"Every citizen should be free to vote without interference and to have his or her vote count, without the fear that it will be stolen because of fraud," Bentley said. "The Department of Justice will act promptly and aggressively to protect the integrity of the voting process."

In August, former U.S. Attorney General Eric Holder sent a strongly worded letter to Gov. Scott that said the Justice Department will be "carefully monitoring" Florida voting.

At the time, Scott called Holder's letter "pure politics," and said it was "just them trying to help Charlie Crist."

Scott's campaign issued a statement Wednesday that said: "We want 100 percent voter participation and zero percent fraud."

For nearly a month, Florida voters have been casting ballots with few reported problems.

Four days of early voting remain in many counties. Through Tuesday, nearly 2.2 million Florida voters had voted by mail or at an early-voting site.

Scott and Crist are both aggressively promoting early voting. Scott is in the second week of a two-week bus tour and Crist is traveling across the state.

Democrats will make a final push Sunday to get as many black voters as possible to the polls after church, a program called "Souls to the Polls."

More people have already voted by mail or in person in Pinellas County than did in the 2010 election for governor. Through Wednesday, 28.2 percent of all Pinellas voters had already cast ballots.

Prosecutor Bentley, 55, was nominated in June by President Barack Obama to be the top federal prosecutor in a region that spans 35 counties and includes more than half of Florida's population from Jacksonville to Naples.

Bentley is a registered Republican and has been a federal prosecutor in Florida since 2000.

Efforts to protect voters from possible civil rights violations are also under way by U.S. attorneys in North and South Florida.

Miami Herald staff writer Marc Caputo contributed to this report. Contact Steve Bousquet at bousquet@tampabay.com or (850) 224-7263.