The Texas Democratic Party charged that Sen. Hillary Clinton's campaign "threatened" to challenge aspects of the state's two-step nominating process, just days before Tuesday balloting, which now appears unlikely to produce the blowout victory the New York senator needs to stay in the race.

Among other things, party activists said the Clinton campaign was trying to delay the release of the results from that evening's caucuses, where Illinois Sen. Barack Obama is thought to have an advantage. A delay in reporting those results...