By Jeff Mayers MADISON, Wisconsin (Reuters) - A judge temporarily blocked enforcement of Wisconsin's controversial new voter identification law on Tuesday, weeks before the state's April 3 presidential primary, and supporters of the law said they would likely appeal. The law, passed last year by a Republican-controlled legislature, requires voters to present photo identification such as a driver's license at polling places for federal, state and local elections. Dane County Judge David Flanagan issued the temporary injunction as part of a lawsuit brought by the National Association for the Advancement of Colored People, which argued the law disenfranchises voters who do not possess acceptable identification, many of them minorities. Thirty states now require voters to show some form of ID before voting, according to the National Council of State Legislatures. In 14 of those, including Wisconsin, the ID must include a photo of the voter. Advocates of the laws, which also passed last year in Alabama, Kansas, Rhode Island, South Carolina, Tennessee and Texas, say they are needed to combat voter fraud. Opponents say there is no evidence of widespread fraud, and that the measures suppress the votes of ethnic minorities, the elderly and the poor. Efforts to overturn the laws have generally been unsuccessful so far. Indiana's law was initially blocked but later reinstated by higher courts. But Flanagan said in his ruling that Wisconsin's law was more restrictive than laws in other states that have survived federal court scrutiny. He said evidence presented by the NAACP documenting the problems that 40 qualified voters had experienced as they tried to comply with the law had compelled him to grant the injunction. "The 40 uncontested affidavits offer a picture of carousel visits to government offices, delay, dysfunctional computer systems, misinformation and significant investment of time to avoid being turned away at the ballot box," he wrote. Flanagan ordered state officials to stop enforcing the law, pending a trial scheduled to begin on April 16, nearly two weeks after voters in the state will have cast their ballots in the presidential primary. The Wisconsin state Department of Justice said it would likely file an appeal and hoped to have the voter ID requirement in place for the April 3 presidential primary and spring elections in the state. "We disagree with the ruling and will continue our efforts to defend Wisconsin's voter ID law, which is similar to laws that have already been upheld by the United States Supreme Court," spokesman Dana Brueck said. The Government Accountability Board, which administers elections in Wisconsin, said other key provisions of the law remained in effect, including a requirement that voters be residents for 28 consecutive days and sign the poll list. The photo ID law was part of an ambitious agenda championed by Republican Governor Scott Walker last year that split the state along partisan lines and triggered a round of summer recall elections. Opponents of Walker's agenda, which also included curbs on public sector unions, spending cuts and an easing of restrictions on concealed weapons, last year launched a signature-gathering effort to force the governor to defend his seat in a special election. In January, they submitted what appeared to be more than enough signatures to force a recall. Walker has said he would not challenge the signatures, and it is up to the accountability board to determine if and when an election must be held. Reaction on Tuesday to Flanagan's move was predictably split. Christine Neumann-Ortiz, the executive director of Voce de la Frontera, which joined the NAACP in challenging the law, called the decision an affirmation of the "sanctity of voting rights" in Wisconsin. "It's fundamental to any democracy that people have a voice," she said. We really feel this is more than a legal challenge. I think there is a movement that we certainly want to encourage of protecting our voting rights. Republican state Representative Jeff Stone, an advocate of the voter ID law, said he was confident that photo ID would ultimately be reinstated. The state Republican Party issued a statement saying Flanagan should have recused himself because he supports the effort to recall Walker and said it would file a complaint with the Wisconsin Judicial Commission. Republicans provided a copy of a recall petition page that included the signature of a David Flanagan living at a Madison address matching the address the judge listed on his campaign registration statement filed with the accountability board. A source close to Flanagan confirmed he signed the recall petition. Additional reporting by Marie Rohde; Writing by James B. Kelleher; Editing by Paul Thomasch, Greg McCune and Cynthia Johnston