A Puerto Rican legal advocacy group late Tuesday sent a trove of documents from Supreme Court nominee Sonia Sotomayor's past to the Senate panel considering her nomination.

Latino Justice PRLDEF sent the Judiciary Committee more than 350 pages of documents from the 12 years Sotomayor spent on its board, opening what could be an ugly new chapter in the debate over confirming the federal appeals court judge as the first Hispanic justice.

The documents were not immediately available, and committee aides confirmed their receipt on condition of anonymity because they were not authorized to discuss them publicly.

Republicans, who have criticized Sotomayor's involvement in the group and called it radical, signaled they were searching for clues in the documents about her stances on the many hot-button issues the civil rights organization handled.

A GOP Judiciary aide said the material details PRLDEF's opposition to failed conservative high court nominee Robert Bork, and its ties to the community-activist group ACORN.

Republicans and Democrats teamed to request the documents, and GOP senators have suggested the delay in uncovering them is grounds for delaying hearings on the nomination, now set to begin on July 13.

Earlier Tuesday, Cesar Perales, PRLDEF's president and general counsel, said he was planning in the coming days to send the Judiciary panel several batches of meeting minutes from Sotomayor's period of service from 1980 until 1992, as well as pleadings from cases it handled while Sotomayor headed the board's litigation committee.