Bahrain's Shia Muslim opposition has won at least 40% of the vote in elections which saw women and liberal candidates fare poorly.
Campaigning for this election has been vigorous
The results will give a greater say to majority Shias in the Gulf state, where there have long been tensions between them and the ruling Sunnis.
It is only the second time people have been able to vote for national MPs.
No group got enough votes for an outright majority, and there will be run-offs for several crucial seats.
But so far, the main Shia opposition group, Al Wefaq, has taken 16 of the 17 seats the group was contesting.
The group's leader was circumspect about the results.
"Our participation is limited," Sheikh Ali Salman told Reuters news agency.
"It's a positive step but let's put this participation in perspective. There are 40 people appointed by the king with the same legislative powers."
It was the first time Al Wefaq had taken part in elections. The group boycotted a 2002 vote arguing that constitutional change had not gone far enough.
The result four years ago was a parliament of mostly pro-government MPs.
This time the Shia group will be in a position to try to make changes from within government institutions, says BBC Gulf correspondent Julia Wheeler.
Men and women over the age of 20 years can vote
Voters: Population of 700,000, plus resident citizens of Gulf States
Political parties banned, so candidates are organised into "political societies"
National Assembly made up of 40 appointed and 40 elected members
Only one woman who ran unopposed was elected out of 18 standing, and no secular liberal candidates won seats outright.
Turnout was reported to be high at 72%, and one official hailed the results as proof that the elections had not been rigged.
On Friday, about 2,000 people protested in the capital Manama demanding the resignation of Prime Minister Khalifah bin Salman al-Khalifah over alleged electoral fraud.
The former government adviser who made the allegations has been deported.
Salah al-Bandar had accused the government of plotting to ensure Sunni Muslim dominance in the elections.
The Shura Council, which is appointed by King Hamad, ultimately has the final say over any legislation put forward by MPs.