The second ruling declared unconstitutional legislation that the Islamist-dominated Parliament had passed, known as the political isolation law, that banned members of Mubarak’s government from running for the presidency. The law was introduced after Shafik, a retired air force general who was Mubarak’s last prime minister, had registered to run for president. The court said it was an impermissible limitation on a specific individual who’d broken no other laws.

It was uncertain how the rulings would affect voting in this weekend’s runoff for the presidency, which pits Shafik against the Muslim Brotherhood’s Mohammed Morsi. The matchup – balloting will take place Saturday and Sunday – has dismayed the secular revolutionaries whose demonstrations led to Mubarak’s resignation since it was decided in voting last month.

The revolutionaries are loath to vote for Shafik as a holdover of the old regime, but they fear that a Morsi victory would concentrate too much power in the Muslim Brotherhood’s hands. The losing candidates who generally drew the revolutionary vote in the first round declined to endorse either candidate.

Hamdeen Sabahi, an Arab nationalist and revolutionary favorite who came in third in the first round and won in Cairo and in Alexandria, Egypt’s second largest city, angered his supporters Thursday by calling for Egyptians to "respect the judiciary."

Others said the rulings should be viewed with suspicion.

“The rulings undermine the credibility of this weekend’s balloting, further jeopardize the reputation of Egypt’s traditionally respected judiciary and raise the specter of a new round of mass demonstrations,” the Washington Institute for Near East Policy concluded.

Analysts who were trying to understand how a revolution that had begun with such democratic hopes could appear to be foundering at what should have been its most triumphant moment – the democratic election of a president to replace the military council – questioned the revolutionaries’ effort to use Mubarak-created institutions to carry out change.

Akl said the ruling military council methodically had leveraged those institutions over the months to increase its powers. The revolutionaries, without a unified platform or single leader to develop alternatives, embraced the system that was already in place. They endorsed elections, participated in the constitutional assembly and “legitimized the process,” he said.

Immediately after the rulings Thursday, a small crowd gathered at Tahrir Square, far fewer than the thousands who’d met just two weeks ago to express outrage at the exoneration of Mubarak’s top aides in the deaths of hundreds of demonstrators during last year’s uprising. It was unclear whether the revolutionaries had decided that protests were no longer an effective response to the state’s political and legal maneuvering or whether they were simply planning their next move for Friday, a traditional day of protest.

The Muslim Brotherhood, with 47 percent of Parliament seats, appeared to lose the most by the rulings. Yet it wasn’t prepared Thursday to reject the system. In a television appearance Thursday night, Morsi said: “I don’t see what is going on as military coup,” adding, “I love the armed forces.”

Mahmoud Ghouzlan, a Muslim Brotherhood spokesman, told McClatchy shortly after the rulings that the Brotherhood would run again in the next parliamentary elections, whenever they are.

The court rulings are “a fact, and we have to deal with it,” Ghouzlan said.

For his part, Shafik celebrated.

"The ruling of the constitutional court today allowing me to continue running for the presidency has put an end to the era of personal vendettas and tailoring laws, an end to the humiliation of the legal system," Shafik said.

An election official whom McClatchy reached immediately after the midday rulings said officials there were proceeding normally.

In the hours before the verdicts, military officers had driven through neighborhoods in armored personnel vehicles, handing out fliers urging Egyptians to vote this weekend, suggesting that the ruling military council had assumed the election would proceed regardless of the ruling.

McClatchy special correspondents Amina Ismail and Mohannad Sabry contributed to this report.