After two humdrum rounds of legislative elections, Lebanon is poised for a heated contest Sunday that could determine whether an anti-Syrian coalition will muster a parliamentary majority and maintain momentum to thrust the country into a new era.

In the most critical round of a four-phase election, Christian and Muslim voters in the central Mount Lebanon region and the eastern Bekaa Valley will decide on nearly half of the 128 seats in parliament.

At stake domestically is the new legislature's ability to dislodge remnants of Syrian control, after a 29-year military presence, from key institutions including the presidency. Syrian troops withdrew from Lebanon this spring, but the country continues to wield considerable influence.

"Syria is out of our geography, but not out of our politics or the region's geopolitics," Rafik Khoury, a columnist with the Al Anwar daily newspaper, said in an interview. "The difference is that a year ago, we were on death row. Now our sentence has been reduced to a one- or two-year prison term."

Also at stake will be the legislature's ability to maintain a fragile national unity movement and push through political and economic reform.

Regionally, Lebanon could emerge as a showcase for progress through democratic means, for which the United States could be credited for playing a constructive role.

Politicians opposed to Syrian influence won big in the first phase in Lebanon's capital, Beirut. Hezbollah, the Syrian-allied Shiite guerrilla group, and its allies won in the second round in southern Lebanon. The voting will conclude June 19.

The elections have gained urgency since the assassination on June 2 of a journalist who championed a years-long crusade against Syrian involvement. Samir Kassir was killed in a car bombing outside his home, 31/2 months after the assassination of a former prime minister, Rafiq Hariri, in a bombing in the capital.

The electoral drama has been fueled by allegations from some opposition and U.S. officials that Syria has developed a hit list targeting senior Lebanese political figures in an attempt to regain control.

"We have received tips on these threats from our own sources in Syria as well as Arab and some Western sources," said Marwan Hamadeh, a former government minister. "Syria's aim is to plunge Lebanon again into deep chaos and crisis because it finds itself in total distress."

Lebanese viewers have been treated to lively televised debates and talk show appearances by pivotal figures in the opposition and their opponents. Many of the 100 candidates have also taken to the road, appearing at festive rallies in far-flung villages and townships.

On one side is Walid Jumblatt, the leader of Lebanon's small Druze Muslim community and a longtime power broker whose alliance with Hariri's son, Saad, is expected to dominate the next parliament. Hariri, campaigning from behind bullet-proof glass shields, has traveled to northern towns and Shiite-Sunni Muslim townships in the Bekaa Valley to draw support for allied candidates.

That coalition will lock horns with candidates allied with Michel Aoun, a retired general who has allied himself with pro-Syrian politicians. Aoun, a Christian, returned from exile in France last month at the request of Jumblatt, Hariri and Christian politicians seeking more religious balance in the campaign. Aoun has since broken ranks with the opposition, determined to position himself for the presidency.

"These alliances are more about elections than they are about politics," said Kamal Feghali, an elections specialist and authority on demographics.

Aoun's move splintered the Christian vote and deprived the opposition of the religious diversity manifested on March 14, when more than 1 million Lebanese gathered in a peaceful demonstration and a show of unprecedented national unity after Hariri's assassination. Aoun also refused to go along with opposition demands to unseat Lebanese President Emile Lahoud after Kassir was killed. Lahoud's six-year term was extended for another three years under pressure from Syria.

Aoun, who rarely appears without a phalanx of bodyguards, has cast himself as a national healer of wounded spirits and the infirmities of a failed state. "If you want salvation, follow me," he said recently.

"This Lebanon cannot be sold to other countries through brokers," he said to voters in a familiar tirade against the "petrodollars" of the ruling elite, a snipe at Hariri, whose father amassed his fortune in Saudi Arabia.

Aoun's political fortunes remain a mystery. "Aoun is still an untested electoral force. This weekend will tell whether he is a tsunami or a bubble that will burst," said Hani Hammoud, editor in chief of al-Mustaqbal, a daily newspaper founded by Rafiq Hariri. "Right now, he is in bed with Syria's allies. We don't know how he will vote once he is elected."

To many Lebanese who saw the withdrawal of Syrian forces as a chance for new beginnings, the election has come as a disappointment. "I feel political change will happen very gradually. The 2009 election will be our real test," said Nora Mourd, a board member of the Lebanese Association for Democratic Elections, which has 700 volunteers monitoring the elections.

The group, founded in 1996, has concluded that the campaign so far has been largely free and fair, with only minor irregularities.

Mourd said Lebanon was still "way ahead of its neighbors in the practice of democracy. We don't have a one-party system, but we are still trying to enhance the role of political parties."

Feghali said there was still little understanding that a system was needed that could "rule out extremists to safeguard minorities."

Hassan Nasrallah, the secretary general of Hezbollah, surprised many Lebanese during a rally this week by vowing that he and his followers wanted to be part of a "real partnership" with the rest of their countrymen in modernizing institutions and confronting economic challenges. But the larger question remains: whether the group will eventually agree to disarm. Hezbollah is expected to win as many as 14 seats in the election.

Special correspondent Alia Ibrahim contributed to this report.

Supporters of former Lebanese Gen. Michel Aoun rally in a Beirut suburb. Aoun was encouraged to return from exile to join an opposition alliance, but broke ranks and sided with pro-Syrian forces.A man expresses support for Aoun, depicted in a poster, right, during a rally. Aoun is challenging an opposition alliance seeking independence from Syria.Walid Jumblatt is the leader of Lebanon's small Druze community.