TUNIS, Jan 21 (Reuters) - For years they were jailed or exiled. They were excluded from elections, banned from politics, and played no visible role in Tunisia's Jasmine Revolution.
But in the brave new world of multi-party politics, moderate Islamists could attract more followers than their secular rivals like to admit.
And the downfall of Zine al-Abidine Ben Ali's police state may leave Tunisia open to infiltration by extremists from neighbouring Algeria, where war between authorities and Islamists has killed 200,000 people in the last two decades.
"The Islamist movement was the most oppressed of all the opposition movements under Ben Ali. Its followers are also much greater in number than those of the secular opposition," said Salah Jourchi, a Tunisian expert on Islamic movements.
"Its effect could be large."
Secularism has been strictly enforced in Tunisia since before its independence from France in 1956. Habib Bourguiba, the independence leader and long-time president, was a nationalist who considered Islam a threat to the state.
Indeed, in 1987, when Ben Ali pushed aside Bourguiba, he briefly released Islamists from jail and allowed them to run in the 1989 elections. The results surprised and worried Ben Ali.
Ennahda, or Renaissance, Tunisia's largest Islamist movement, officially won 17 percent of the vote, coming second to the ruling party.
Jourchi said there was widespread electoral fraud and the real figure could have been closer to 30-35 percent. That compared with a combined total of three percent for all the secular opposition parties that ran in the same elections.
Ben Ali reversed his policy, banned Ennahda, jailed its followers and cracked down harshly on anyone showing any tendency towards Islamism. Ennahda's leader Sheikh Rachid Ghannouchi was exiled to London the same year.
Ghannouchi, who declared his desire to return to Tunisia soon after Ben Ali's ouster, has yet to set a date.
But now that Tunisia's interim government has agreed an amnesty law that allows banned parties and frees political prisoners, Ghannouchi could return any day.
Husain Jazeery, an Ennahda spokesman exiled in Paris, said the movement would take part in parliamentary elections expected to be held in the next six months but would field no candidate for the presidency because "we do not want to rule the country".
"We are a party that does not want to rule but wants to take part alongside all the other groups and to do so responsibly," he said by telephone.
"Any exclusion of Ennahda would be a return to the old regime and that would be impossible in the current situation ... regardless of internal or external pressures."
Despite the state's crackdown on Ennahda, the movement is considered moderate and could draw widespread support.
Ghannouchi, a respected scholar, teaches that Islam is compatible with democracy. Having lived in London for over 20 years, he also advocates dialogue with the West.
That view was repeated by worshippers at the Quds mosque in Tunis, many of whom identified themselves as Islamists though they wore Western suits, spoke French and were clean shaven.
"Tunisia is a small country but it has room for everyone and everyone's ideas. They thought there would be chaos in Tunisia but we are united. We do not have Shi'ites, Christians, Jews. We are all Sunni Muslims and this unites us," worshipper Rida Harrathi told Reuters before Friday prayers.
"Of course Ennahda will play a big role in the elections. It is from the people. It did not come from outside, from another planet. It is part of us and these people made a big sacrifice, as did the honourable members of the communists and the unions."
The end of Ben Ali's rule could see a marked growth in the outward expression of faith.
Bourguiba, who saw himself as a modernising leader akin to Turkey's Kemal Ataturk, famously called the veil an "odious rag". He seized properties held by Islamic trusts, closed their courts and enshrined secular family codes.
Under Ben Ali, women who covered their hair in the Islamic tradition were denied access to education and jobs.
Many say police used to stop them in the streets, strip them of their headscarves and force them to sign papers renouncing the veil. Men with long beards were similarly treated.
"If they change the laws I would wear a headscarf. I know a woman who worked here who kept wearing the headscarf and her wages were docked," said Lutfiya, a hotel worker who declined to give her full name as she was not authorised to speak.
"If you wear the hejab it does not mean you will make chaos and terrorism. If I wear it I will still look after my country."
But many fear that with police rule ended and open politics introduced, extremist ideas will circulate as openly and as widely as democratic or secular ideas.
In 2002, al Qaeda claimed responsibility for a truck bombing of a synagogue in Tunisia which killed 21 people including 14 German tourists. In 2006-7 security forces rounded up men accused of being Salafists, who have a strict interpretation of Islam.
Jourchi said he expected the Salafist voice to be drowned out in the clamour for free expression in the coming months and for the more moderate voice of Ennahda to draw more adherents.
"Qaeda and its ilk do not rely on large numbers or populism but on small groups who carry out violent acts," he said.
Outside the Quds Mosque, worshippers said the threat from al Qaeda was overstated by the West and this had been used as an excuse to curtail freedoms and prop up Arab tyrants.
"We are open people. We are a people that has been open to all civilisations since the dawn of time," said Shawki, a 34-year-old doctor.