Federal MPs have finished a marathon 22-hour voting session on changes to the government's omnibus implementation bill, considering more than 800 amendments.

The hundreds of amendments were grouped into 157 votes by House Speaker Andrew Scheer. MPs had begun the voting process around 1 a.m. Thursday and finished 22 hours later at about 11 p.m.

Opposition MPs felt Bill C-38 was too broad in scope and had wanted it broken apart into separate pieces of legislation. They were especially concerned with faster environmental approvals of mining and oil projects, and changes to the Fisheries Act, Employment Insurance and Old Age Security.

The OAS changes aren't scheduled to take effect until 2023.

Although the bill was certain to pass, opposition parties slowed the process down by introducing scores of amendments.

"If we had simply allowed this government to pass this bill without any inconvenience at all, the lesson they would have taken away and Canadians would have taken away is that Parliament is less important than it really is," NDP House Leader Nathan Cullen told reporters earlier Thursday.

"We must hold government to account. That is our job, that is what Canadians sent us here to do."

Finance Minister Jim Flaherty said the 425-page bill is "responsible, necessary and will make Canada's economy stronger," and he called the amendments introduced by the opposition "non-substantive."

MPs arrived early Thursday morning armed with snacks, blankets, pillows, and even iPads. They organized in shifts to ensure each party had enough members in the Commons at any given time during the voting marathon.

The Conservatives, for example, split their MPs into 11 groups, with 10 of the groups required in the Commons at all times. As a result, all MPs got a short break at regular intervals to use the bathroom, get a coffee or stretch their legs.

Liberal MP Marc Garneau tweeted Thursday morning that he could smell bacon being cooked somewhere in the House of Commons: "I remain focused like a laser," he added, with the hashtag #BudgetFAIL.

Both sides of the budget showdown said they had the support of Canadians.

"The feedback we've been getting on social media, on Twitter and Facebook, it's been heart-warming," said Cullen. "The messages coming in have been beautiful. They steel your resolve a bit to know that people appreciate that when the country is being bullied, our Parliament is being bullied, that there's someone who's going to push back."

However, Treasury Board President Tony Clement told CTV's Power Play that some members of the public wanted the bill passed, such as small business owners who will receive tax credits to hire people and municipalities that will have access to the gas tax in perpetuity.

"There's all these groups where they see an economic benefit that will create jobs, that see the value of this bill," Clement said.