Texas' plan to subsidize private health coverage for working-poor adults has hit a snag, as federal health officials have questioned whether the state's proposal to overhaul Medicaid moves quickly enough to cover uninsured workers and is sweeping enough to justify bending federal rules. A federal official outlined the reservations in a recent letter to state officials. Some healthcare lobbyists said that the letter's tone suggests state leaders may not be able to get federal approval before President Bush leaves office.