Thursday night鈥檚 election debate was lively and largely on-script, with each of the party leaders stealing the spotlight at one point or another, and no clear winner emerging from their first election showdown.

Conservative Leader Stephen Harper, NDP Leader Thomas Mulcair, Liberal Leader Justin Trudeau and Green Leader Elizabeth May each had some strong moments, but there were no knockout punches in what is, so far, the only English-language debate with all four individuals present.

The debate鈥檚 format seemed to benefit Stephen Harper the most, according to Christopher Waddell, a professor at the Carleton School of Journalism.

鈥淧ast debates have tended to be all the parties ganging up in a series of one-on-one encounters, and they tend to gang up on whoever is in power,鈥 Waddell told CTV鈥檚 Canada AM on Friday. 鈥淭his time, I think he didn鈥檛 face nearly as much as that.鈥

Thursday night鈥檚 format saw moderator Paul Wells pose a question to one of the leaders to answer, before opening the floor up for discussion. The format resulted in a lot of interjections and shifts in attention, as the leaders selectively attacked their targets.

Each candidate 鈥渄id really well鈥 in the debate, according to Antonia Maoini, a political science professor at McGill University.

Waddell added that it鈥檚 likely too early in the campaign for this debate to 鈥渟et the tone鈥 going forward, especially considering the size of the audience. 鈥淚 don鈥檛 think there was a huge audience,鈥 he said.

Here鈥檚 a look at how each leader performed during the debate.

Thomas Mulcair

Maoini said Thomas Mulcair had good content and 鈥渁 lot of good zingers,鈥 but he failed to bring the fire that earned him the nickname 鈥淎ngry Tom鈥 in the House of Commons.

鈥淗e went from 鈥楢ngry Tom鈥 to Dozy Tom,鈥欌 Maoinin told Canada AM. 鈥淢ost of the debate he just looked a little off, and just had a smile pasted on his face, but not a lot of passion or energy,鈥 she said.

Waddell suspected Mulcair鈥檚 restraint was an attempt to blunt voter worries that the NDP are too 鈥渆xtreme鈥 to hold power.

Mulcair mostly stayed out of the heated back-and-forth exchanges that May and Trudeau seemed to dive into headlong. On multiple occasions, the moderator had to step in to ask Mulcair for his point of view, silencing the other leaders.

Despite his subdued presence, Mulcair still delivered several challenging attacks on his opponents.

Maoini said Mulcair was particularly 鈥渃lever鈥 to focus his attacks on Harper鈥檚 economic record. 鈥淗e kept mentioning the word 鈥榡obs,鈥 over and over again,鈥 she said. She suggested Mulcair will continue to attack Harper on the economy and jobs throughout the campaign.

Despite Mulcair鈥檚 reserved tone, he still showed some of his House of Commons fire in attacking Justin Trudeau on the issue of Quebec sovereignty. Mulcair repeatedly demanded to know how many votes Trudeau would want from the Supreme Court before allowing Quebec to separate from Canada. 鈥淲hat鈥檚 his number?鈥 Mulcair repeated, while hammering at Trudeau over Quebec sovereignty.

鈥淵ou want a number, Mr. Mulcair?鈥 Trudeau finally answered. 鈥淚鈥漧l give you a number. My number is nine.鈥

Mulcair also claimed a few small victories against Stephen Harper, including pressuring him to admit that the country鈥檚 GDP has declined in five straight months, putting it on the verge of a recession. The technical definition of a recession, as Mulcair pointed out, is six consecutive months of declining GDP numbers.

鈥淪tephen Harper is the only Prime Minister in Canadian history who, when asked about the recession during his mandate, gets to say 鈥榃hich one?鈥欌 Mulcair said.

In his closing statement, Mulcair suggested Canadian voters face a two-party choice between Harper鈥檚 Conservatives and his NDP.

Justin Trudeau

Maioni and Waddell were divided over their evaluations of the Liberal Leader. Maoni felt Trudeau exceeded the low expectations set for him heading into the debate, while Waddell suggested he focused too much on delivering quotes for TV, and not enough time explaining Liberal policies.

鈥淭o me, he spent most of the night talking in points that he hopes will be picked up on news clips,鈥 Waddell said. 鈥淚f you were watching the debate to find out much about what Liberal policies were, I don鈥檛 think you discovered a lot.鈥

Maioni had more praise for the Liberal Leader. She said Trudeau 鈥渟howed quite a bit of depth鈥 and demonstrated a mastery policy issues 鈥 an area that some might have been concerned about with him.

Trudeau preached his party鈥檚 middle-of-the-road approach through much of the night. 鈥淵ou cannot make a choice between what鈥檚 good for the environment and what鈥檚 good for the economy,鈥 he said during the environment debate.

Later, he defended his party鈥檚 support for the much-criticized Bill C-51, saying his party would strike a balance between keeping people safe and defending their rights and freedoms.

鈥淲e supported that legislation because there were specific elements in there that immediately and concretely protect Canadian security, and we鈥檙e committed to repealing the problematic elements that have been highlighted,鈥 he said.

Trudeau was also one of the more combative participants, interjecting with 鈥渢hat鈥檚 not true, Mr. Harper,鈥 and 鈥渘obody believes you鈥 multiple times while the CPC Leader was speaking.

Stephen Harper

Stephen Harper held up well against the slings and arrows hurled his way on Thursday, Maoini and Waddell agreed. Harper recited many of the defences he鈥檚 used in recent months, citing a balanced budget when questioned about the economy, and promising that the country鈥檚 scandal-plagued senators would be held 鈥渁ccountable鈥 for their 鈥渂ad actions.鈥

鈥淢r. Harper did what he wanted to do, which was to look prime ministerial, and to allow the other leaders to fight one off the other,鈥 Maoini said.

Harper deftly stickhandled around a pointed question about the Senate, in which he was asked if he should apologize for the actions of suspended senators Patrick Brazeau, Pamela Wallin and Mike Duffy, all of whom were appointed during his tenure.

鈥淢y role is not to apologize for the bad actions of others,鈥 Harper said. 鈥淲hen problems arise, the role of a leader is to take responsibility and hold people accountable, and that鈥檚 exactly what we鈥檙e doing.鈥

Moderator Paul Wells managed to put Harper on the spot at one point, when he pressed the Conservative Leader on whether he asked Conservative-appointed senators to kill a bill passed by the House of Commons. 鈥淲hat we ask them to do, Paul, is we ask them to support the party鈥檚 position. The party did not support that particular bill,鈥 he said.

Maoini pointed out that Harper seemed to lump his opponents together as 鈥渢he other guys鈥 during the debate. 鈥淚鈥檒l tell you what won鈥檛 grow the economy: the kinds of plans these guys are proposing,鈥 Harper said.

Maoini added that Harper gave the impression of being a steady hand behind the wheel, able to stay above the fray of the debate.

Waddell said he was surprised by Harper鈥檚 potentially problematic focus on Justin Trudeau, at the cost of attacking Thomas Mulcair.

鈥淚 wonder whether, in fact, he鈥檚 suffering from a little bit of the narrow focus that the Alberta Conservatives suffered from in the provincial election in Alberta, where鈥 they didn鈥檛 think the NDP was a serious competitor,鈥 Waddell said. 鈥淚鈥檓 not sure that was really the right focus for him, but it鈥檚 early in the campaign.鈥

Maoini said Harper seemed to be more comfortable attacking Trudeau than taking on Mulcair. 鈥淚 think that鈥檚 why in this first debate, he wanted to come out winning on that side,鈥 she said.

Elizabeth May

Maioni and Waddell echoed one another in their simple evaluation of the Green Party Leader: 鈥淓lizabeth May was Elizabeth May.鈥

The veteran election debater played spoiler of sorts, challenging her opponents on several key issues.

For instance, she drilled Mulcair on his approach to the Kinder Morgan pipeline project, and called for him to take a solid stance against it. Mulcair deflected her demands several times, before concretely stating he would commission an 鈥渙bjective study鈥 of the issue before making any decision on it.

May played to her strengths by hammering Harper over his environmental record, scolding him for pulling out of the Kyoto Accord and failing to stay on track to meet 2020 emission targets.

鈥淲ith all due respect, Mr. Prime Minister, your record on climate is a鈥 litany of broken promises,鈥 she said.

May was also the one to bring up the Climate Accountability Act 鈥 a bill passed in the House of Commons and shot down by Conservative-appointed senators at Harper鈥檚 request they stick to party policy. That discussion opened the door for the other leaders to attack Harper on the issue of the Senate.