Final answer:
The U.S. Supreme Court halted the Florida recount in Bush v. Gore (2000) due to equal protection violations and the lack of time for a constitutional recount, which resulted in George W. Bush winning the presidency.
Step-by-step explanation:
The Florida Supreme Court could not order a recount of ballots in the 2000 presidential election because the U.S. Supreme Court found that the manual recounts as conducted violated the equal protection clause of the Constitution, and there was insufficient time to initiate a recount that would meet constitutional standards. The U.S. Supreme Court ruled in Bush v. Gore, with a 7-2 decision on the equal protection issue and a 5-4 decision on the issue of time, ultimately halting the recount and leading to George W. Bush receiving Florida's electoral votes, securing his presidency. This ruling was controversial and is remembered for its significant political implications and the role of the Supreme Court in the electoral process.