Mudslinging over ethics and a focus on whether another sovereignty referendum would eventually be held dominated the 33-day campaign.
Pauline Marois, whose Parti Quebecois formed a minority government in the 2012 election, is seeking a majority and has expressed optimism her party will form a government.
Recent opinion polls, however, indicated the momentum was with Philippe Couillard's Liberals, with the surveys giving them a shot at taking power when the votes are counted.
The PQ had hoped to capitalize on identity politics, as it did in 2012, by making its secular charter the focus of the campaign.
But that plan was derailed when star candidate Pierre Karl Peladeau announced early in the campaign he had left the business world for politics so he could build an independent Quebec for his children.
Couillard repeatedly tried to exploit the distaste for a third sovereignty referendum at the PQ's expense.
One leader who had cause for some glee is Coalition chief Francois Legault.
Although the Coalition had been badly slipping in opinion polls, Legault saw a rebound after his strong performances in televised leaders' debates.
The former PQ cabinet minister describes himself as a nationalist who wants a moratorium on sovereignty referendums. His party's voters are mostly small-c conservatives who are attracted by his right-wing agenda.
At dissolution, the PQ had 54 of the national assembly's 125 seats, while the Liberals had 49. The Coalition had 18, Quebec solidaire two and there were two Independents.
Marois was the first of the main leaders to vote Monday.
"It is a beautiful day," Marois told reporters after she cast her ballot in the riding of Charlevoix-Cote-de-Beaupre, northeast of Quebec City.
"I am inviting all Quebecers to vote. I am very serene at this moment. I trust Quebecers will choose a good government to lead them and I am confident about tonight."
Legault voted later in his riding of L'Assomption, northeast of Montreal, and also used the word "serene" to describe his mood.
"It's an important day, obviously," he told reporters. "During 33 days, I offered a choice that was different from that of the other parties. I put forward ideas. Now it's up to Quebecers to decide."
Legault admitted to having butterflies as he awaited the outcome of the election.
"The day of an election is always a bit nerve-wracking. You're keen to see the results. But I am very serene."
The polls close at 8 p.m. eastern.