LAHORE, Pakistan ? Tens of thousands of cheering, chanting supporters showered former Prime Minister Nawaz Sharif with rose petals as he triumphantly returned from exile Sunday, posing a thorny new challenge not only to President Pervez Musharraf but also to pro-Western opposition leader Benazir Bhutto.

Sharif’s comeback, just 11 weeks after he was summarily deported by Musharraf, the military leader who once overthrew him, marks a complex new phase in the political turmoil that has gripped the nuclear-armed country, a key U.S. ally, for much of the year.

As Musharraf-decreed emergency rule enters its fourth week, his opponents are jockeying for position, seeking an advantage not only against him but possibly against one another as well. Sharif is more religiously conservative and less overtly friendly to the West than either Musharraf or Bhutto.

“Obviously, it’s huge,” University of Oregon professor Anita Weiss said of Sharif’s return. The author of several books on Pakistan, she said many Pakistanis see in Sharif “a mature, elder” – she paused for emphasis – “male statesman.”

In Lahore, the eastern city that is Pakistan’s political nerve center, Sharif’s backers sought to muster a display of support comparable to the enormous crowds that turned out to welcome Bhutto last month – before her homecoming procession was shattered by a suicide bombing that killed nearly 150 people.

Much of the impetus for Sharif’s return is thought to have come from Saudi Arabia, embarrassed by its role in the previous deportation. Musharraf, who made a 24-hour visit to the kingdom last week, was reportedly told by Saudi officials they were unwilling to risk prestige and popularity by appearing to hold Sharif against his will.

Amid the jubilation Sunday, Sharif’s followers appeared to ignore that he was an unpopular prime minister in 1999, when Musharraf’s coup was widely welcomed. As Pakistan’s leader, he was plagued by accusations of corruption and incompetence.

“It shows how much there is hunger for change,” said Khalid Butt, editor of the Pakistan Observer.