Rose Renfroe, the Democratic challenger in the District 4 Dallas County Commissioners Court race, can use her controversial nickname "Rosita" on the November general election ballot, a judge ruled Monday.

District Judge Curt B. Henderson – a visiting judge from Collin County sitting in for a Dallas County judge who recused himself – denied a temporary injunction sought by Kenneth Mayfield, the incumbent Republican commissioner.

Judge Henderson said in his ruling that the relief sought was moot and that Mr. Mayfield failed to demonstrate he would "likely succeed on the merits at final trial."

Mr. Mayfield filed suit Aug. 31, asking a judge to bar Ms. Renfroe from using the nickname on the Nov. 7 ballot.

The nickname appeared on the March Democratic primary ballot. But Mr. Mayfield and his attorneys argued that Ms. Renfroe began using the nickname only recently to mislead Hispanic voters into voting for her.

The law states that a candidate must be commonly known by a nickname for at least three years before an election to have the name on a ballot.

"She's pandering to the Hispanic vote. That's a fraud," said Mr. Mayfield, noting that she is a blond-haired, blue-eyed Anglo.

Ms. Renfroe's campaign manager and her daughter testified they had known Ms. Renfroe as Rosita for 25 years. Her attorney, Kenneth Molberg, also said he has called her Rosita for years.

But Mr. Mayfield's attorneys pointed out that none of her official documents such as her driver's license bear the Rosita nickname. They also submitted evidence showing that Ms. Renfroe did not use the nickname in news articles detailing her political activities dating to the 1970s.

Ms. Renfroe, who served one term on the Dallas City Council in the late 1970s, also didn't use the nickname while in office or while running against Mr. Mayfield in 2002, the attorneys said.

Tuesday's ruling could make for a close race.

Ms. Renfroe lost to Mr. Mayfield in 2002 by fewer than 3,500 votes. And District 4, which encompasses the southwest part of the county, is about 40 percent Hispanic.

Had Mr. Mayfield won the court challenge, it would have created headaches for the county election office.

The hearing was held four days before overseas ballots were scheduled to be sent out. Bruce Sherbet, Dallas County's elections administrator, testified that having to reprint the ballots would create a major disruption to the general election and cost taxpayers at least $50,000.

He said 95 percent of the general election ballots have been printed as well as all of the early voting ballots because he had to place a bulk order in advance.

Mr. Sherbet's attorney, Grant Brenna of the Dallas County district attorney's office, argued that Mr. Mayfield's late filing of the challenge would create too many logistical nightmares for the county elections office.

"Our problem is not changing the name but the timing," he said. "The plaintiff in this case slept on his rights."

Mr. Brenna said the suit could have been filed as early as March 8.

Mr. Mayfield testified that he was aware Ms. Renfroe used the nickname during her primary race but decided to file the suit only after being urged by a local Hispanic leader to do so.

Carlos Quintanilla of the League of United Latin American Citizens testified that when he learned Ms. Renfroe was not Hispanic, he contacted Mr. Mayfield and urged him to take action.

"We take offense to that," he said.

Mr. Mayfield said the issue has galvanized local Hispanic leaders who will make sure their community knows what Ms. Renfroe has done "to try to fool them."

Ms. Renfroe said she was elated by the judge's decision and called her opponent's challenge a publicity stunt.

"I think that it was just a ploy on his part. He thought he could discredit me and take me off the ballot," she said. "He's desperate and thinks he can't win."

E-mail kkrause@dallasnews.com