(CNN) -- Syria's President Bashar al-Assad looks more isolated with each passing day as his regime continues a bloody eight-month crackdown on pro-democracy protests.





His Arab neighbors signaled their displeasure with him this week by suspending Syria from the Arab League, a stinging blow for a nation that sees itself at the heart of Arab concerns. Jordan's King Abdullah went a step further, telling the BBC he would step down if he were al-Assad, an unusually blunt assessment that followed Western calls for al-Assad to go.





And Turkey, formerly an important ally and trading partner, threatened to cut off electricity supplies to Syria as the European Union moved this week to extend sanctions against more members of al-Assad's circle.





This week, the conflict inside Syria entered a new era when army defectors attacked pro-government targets. That ratcheted up the pressure even more -- the Russian foreign minister was widely quoted as saying attacks on government buildings in Syria resembled "civil war."





So can al-Assad cling to power? Or will he become the fourth leader forced from office in the Arab Spring, following in the footsteps of ousted leaders of Egypt, Libya and Tunisia?





Analysts say that the odds are stacked against Syria's president.





Steven A. Cook, Hasib J. Sabbagh senior fellow for Middle Eastern studies at the Council on Foreign Relations, said it is hard to predict what might come next for al-Assad -- but the pressure is on.





"The kind of traditional support he had externally is clearly crumbling," Cook said. "His prospects this week are worse than they were last week."





Emile Hokayem, senior fellow for regional security at the Bahrain office of the International Institute for Strategic Studies, thinks it highly unlikely al-Assad will hang on to power.





Three main factors will likely contribute to the downfall of Syria's president after 11 years in power, he said.





One is that he has lost legitimacy in the eyes of his own people. "It's hard to see how he would recover his legitimacy after killing almost 4,000 of his countrymen," said Hokayem. The United Nations puts the toll of deaths at well over 3,500 since protests began.





Second is the economy, as sanctions imposed by the West and Turkey start to bite. This matters, said Hokayem, because al-Assad may struggle to keep the support of the country's urban and business elites in Damascus and Aleppo if the economy is failing.





The third factor is security, despite al-Assad's mobilization of the military. Unlike previous challenges to the al-Assad regime, "this time it's the Syrian people leading it and very clearly regime change is their goal and they are not going to accept anything less," Hokayem said.





Shashank Joshi, an associate fellow at the Royal United Services Institute for Defence and Security Studies (RUSI), also doubts al-Assad will survive -- but says it is far from clear what might follow.





The Arab League's decision to suspend Syria, after Damascus failed to abide by a peace deal that had been brokered earlier with the 22-nation league, signals a shift in views that would have looked extremely unlikely even a month ago, he says.





The regime's military is also increasingly over-extended as those fighting against it find footholds in Lebanese and Turkish soil, he said.





Turkey might also choose to intervene more directly, perhaps by creating a buffer zone along its long border with Syria or providing weapons to the rebels, he said.





At this point, descent into civil war could be as likely a scenario as a clean change of regime at the top, he said.





Nonetheless, Joshi cautioned against thinking the 46-year-old's grip on power will be loosened immediately, pointing to the example of Iraq's former dictator, Saddam Hussein.





In 1991, he said, Hussein had just lost a major war, had two no-fly zones, U.N. sanctions and an oil embargo imposed on his country, was facing an enormous Shia uprising in the south, and
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