Tens of thousands of supporters of former Prime Minister Benazir Bhutto gathered in Pakistan's biggest city Thursday to welcome her home from
eight years of exile to the center stage of the country's volatile politics.

Authorities were mounting a massive security operation to protect Bhutto, a two-time premier, from possible attack by Islamic militants on her planned arrival in Karachi on Thursday afternoon.

In the morning, supporters poured from hundreds of buses festooned with the red, green and black flags of her Pakistan People's Party along the highway from the airport into the city.

On the asphalt, crowds of men performed traditional dance routines to music blaring from loudspeakers.

Samuel Azim, a PPP supporter who traveled to Karachi from Faisalabad told AP Television: "We are not going to feel any sort of frightened for the security. We are pretty confident in ourselves."

Omar Iqbal Wala, a Pakistan People Party supporter at Karachi train station said he wants to give Bhutto a "historic welcome".

Bhutto paved her route back in negotiations with President General Pervez Musharraf, who seized power in a 1999 coup. He is promising to give up his command of Pakistan's powerful army if he secures a new term as president.

The months long talks yielded an amnesty covering the corruption cases that made Bhutto leave Pakistan in the first place, and could see the arch rivals eventually team up in a U.S.-friendly alliance to fight al-Qaida and the Taliban.

Before boarding her flight from Dubai, Bhutto told reporters that her homecoming felt like a miracle.

At the main entrance to Karachi airport, where Bhutto was to arrive at about 1 p.m. (0800 GMT), police were holding back a growing crowd of her supporters waving flags and chanting slogans.

Raza Hussain Shah, the officer in charge of the checkpoint at the entrance, said 20,000 police were deployed there and along the route into the city.

Officials said police bomb squads and thousands of paramilitary troops and party volunteers were also charged with maintaining security.

Bhutto, whose two elected governments between 1988 and 1996 were toppled amid allegations of corruption and mismanagement, is vying for a third term if her party can win parliamentary elections in January.

Many Pakistani are skeptical that another Bhutto government would be any more effective than the earlier editions.

However, her party is hoping that 1 million people will turn out Thursday to welcome her to get her campaign rolling.

Few observers expected such a massive gathering. Karachi police suggested about 40,000 party supporters were in the city early Thursday and more were on the way.

But even that represents a turnout few of her rivals could muster.

Musharraf has seen his popularity plunge since a failed attempt to oust the country's top judge in the spring.

The rapprochement with Bhutto appears aimed at boosting his political base as he vies to extend his rule.

He easily won a vote by lawmakers October 6 to give him a new five-year presidential term.

The Supreme Court, however, has ruled that Musharraf's victory can only become official once it rules on challenges to the legality of his re-election.