Reformists, meanwhile, struggled to create an effective minority bloc after large numbers of their candidates — many of whom support better relations with the West — were barred from the race. The United States said the results were "cooked" because of the disqualifications.
Many reform supporters spent election day Friday deliberating whether to vote and give legitimacy to a contest many of them saw as unfair, or boycott and ensure an even stronger conservative domination of parliament.
In the end, Hesam Javadi, a 30-year-old computer technician, voted.
"We can't stop the rain," he said after casting his ballot for reformists at a north Tehran polling station. "But we can at least put an umbrella over our heads in self-defense."
After vote counting through the night, partial results showed hard-liners headed toward maintaining their domination of parliament, as expected. But among them, conservatives who have grown disillusioned with Ahmadinejad appeared to be gaining ground.
If these so-called "moderate conservatives" do well, it could lead to greater friction between parliament and the president. Conservative critics say Ahmadinejad has fumbled efforts to fix the economy of this oil-rich nation — hit by high inflation, unemployment and fuel shortages.
Such conservatives oppose the United States and want to push ahead with Iran's nuclear program, but many of them say Ahmadinejad has been too confrontational with the West, bringing on U.N. sanctions.
In the 144 of parliament's 290 seats decided so far, pro-Ahmadinejad hard-liners won 53 seats and reformists 18, according to results announced by state television and the official news agency IRNA and reports from local officials speaking to The Associated Press.
A slate of conservative critics of Ahmadinejad seized 38 seats so far, according to the results. Another 35 winners were independents whose political leanings were not immediately known.
The results so far pointed to how deeply the reform movement was hurt when Iran's hard-line clerical leadership threw many of its candidates out of the race. Ahead of Friday's voting, the unelected Guardian Council used its powers to disqualify 1,700 candidates on grounds of insufficient loyalty to Islam or Iran's 1979 revolution.
As a result, reformist candidates were running in only about half of the races nationwide, and many of them are little known to the public. The results so far did not include the capital Tehran, where reformist sentiment is strongest.
Reformists, who hold about 40 seats in the outgoing parliament, seek greater democracy at home and better relations with the West. Most want to dramatically reduce the unlimited powers of supreme leader Ayatollah Ali Khamenei and the clerics who can overrule elected bodies like the parliament.
Strict social code
In contrast, the "moderate conservatives," despite their dislike of Ahmadinejad, avidly support the clerical leadership and want to enforce a stricter social code among the public.
A strong showing by them could raise the chances Ahmadinejad will face a conservative challenger in presidential elections next year. Tehran Mayor Mohammad Baqer Qalibaf and former top nuclear negotiator Ali Larijani have been touted as possibilities.
Larijani, who left the nuclear post after differences with Ahmadinejad, won a seat in the clerical city of Qom, according to state television. He may now seek to push out Ahmadinejad allies and become parliament speaker or deputy speaker, giving him a strong position ahead of the presidential vote.
More than 65 percent of the Iran's 44 million eligible voters cast ballots Friday, Interior Ministry spokesman Hasan Khanlou said. That was up from 51 percent in 2004 election when hard-liners took parliament from reformists, after many liberals were barred from running.
Ahead of the vote, supreme leader Khamenei — who holds final say in all state matters in Iran — appeared to give his support to the Ahmadinejad camp. He urged Iranians to elect anti-U.S. candidates and those "who can pave the way for the current government."
In Washington, State Department spokesman Sean McCormack criticized the elections, saying "in essence the results ... are cooked. They are cooked in the sense that the Iranian people were not able to vote for a full range of people."
"We urge Iranian leaders to end interference in future elections, including the 2009 presidential election," McCormack added.
Some 4,500 candidates nationwide ran in Friday's vote. Final results will take days.