A giant image of Jack Layton's face adorns the NDP's campaign bus, an obvious indication that he's front and centre in the NDP campaign.

Those who have seen the leader in person lately have noticed his face is slimmer and it's prompted questions about the state of his health. He was diagnosed with prostate cancer in late 2009 and went public with it in February 2010. It's the same disease that struck his father (a former Cabinet minister in the Brian Mulroney government) and Layton vowed to face it with determination and optimism.

"Like my dad, I am a fighter and I am going to beat this," he said at the time. Layton has never talked publicly about his specific course of treatment but hasn't shied away from talking about his prostate cancer and working to raise awareness about it.

At times he's looked gaunt and would be forced to wipe a sweaty brow while surrounded by reporters in the foyer of the House of Commons, but through it all, Layton barely slowed down. He's known to be a workhorse, and the nickname "Energizer Bunny" is applied to him more often than to any of his political rivals.

A hairline fracture of his hip recently threatened to interfere with his notoriously hectic schedule, but Layton was back on Parliament Hill within days of having hip surgery in early March. A walking cane was the only clue he was recovering from the surgery.

Layton patiently answered questions about his health in the days leading up to the campaign, saying his doctors monitor his cancer on an ongoing basis and are "happy with how things are going."

Campaigns are grueling, however, especially if someone is not in his usual fighting form. Still, Layton says he's feeling better every day and that he doesn't expect his health issues to alter his party's campaign plan.

Layton is considered one of the NDP's best assets. He's generally viewed as a likeable, trustworthy leader, and the NDP will be putting him front and centre during the campaign to try to increase the party's overall popularity.

Layton was a centre of attention during the pre-campaign weeks on Parliament Hill. It was predictable that the Liberals and Bloc Quebecois were not going to get what they wanted in the federal budget, so speculation turned to whether there would be enough in it to entice the NDP to support it. Layton had made his list of demands clear to the Conservatives — pension reform, more doctors and nurses, lifting the GST off home heating costs, help for seniors and action on the environment — and the budget included spending on some of those fronts.

But it wasn't enough. The NDP leader surprised many observers when he immediately rejected the budget after it was delivered March 22. Layton said the Conservatives failed to make the right choices that would benefit hardworking Canadians. He said he was willing to work with Prime Minister Stephen Harper to amend it, but his offer was rebuffed.

Layton then threw his support behind the Liberals' motion of non-confidence which ended up triggering the election before a vote on the budget could.

Vital Signs

Born: July 18, 1950, in Montreal.

First elected to Parliament: 2004

Profession: Political writer, municipal councillor, politics professor; BA from McGill University in 1970, MA and PhD from York University in 1984.

Personal stuff: Married to fellow MP Olivia Chow. Father of two and proud grandfather.

Layton's called himself a fighter, and he'll be battling fiercely for votes as he criss-crosses the country during the campaign. The NDP has steadily improved its results over the last few elections and it intends to build on that success and grab more than the 37 seats it won in 2008. 

The NDP leader is no stranger to political battlegrounds; he's been in the game for a long time time, and, it's in his blood.

Walking in their footsteps

There are a number of politicians and activists in Layton's family history. His great-granduncle William Steeves was a father of confederation. His great-grandfather Philip Layton came to Canada from Britain as a blind teenager and helped pressure the federal government to bring in a $25-a-month pension for the blind. His grandfather Gilbert Layton was a cabinet minister under  Maurice Duplessis and his father Robert Layton was a Tory cabinet minister in Brian Mulroney's Conservative government.

Layton started honing his credentials as an activist at an early age. In his teens in the 1960s, he led a fruitless bid to have a youth centre built in his hometown of Hudson, Que. He would go on to immerse himself in anti-poverty issues, as well as fights for better public transportation and affordable housing.

That last area of interest led him to write a book, Homelessness: The Making and Unmaking of a Crisis, which was published in 2000. He's also the author of Speaking Out: Ideas That Work for Canadians.

Layton studied politics at York University, earning a PhD there, then began practicing it in 1982 when he was elected to Toronto city council. He made a run for mayor in 1991 and lost.

Two years later, he tried to make the jump to federal politics, following in his father's footsteps, and lost. He tried again in 1997 and lost.

Layton kept fighting. He was elected leader of the federal NDP in 2003, and third time running was the charm: he won a seat in the House of Commons in 2004. Layton defeated Liberal Dennis Mills and has represented Toronto-Danforth since.

His wife, Olivia Chow, joined him as an MP in Ottawa in 2006, when Layton led the party to 29 seats.

The NDP has yet to come near power, except in 2008 when the opposition parties threatened to form a Liberal-led coalition, with the intention of bringing down Prime Minister Stephen Harper's minority government. The Liberals promised that its MPs, and likely Layton himself, would have cabinet positions if the Harper government was toppled but it did not work out that way. Amidst high drama in Ottawa, Governor General Michaëlle Jean agreed to prorogue Parliament and a confidence vote was avoided.

Under Layton, the NDP has climbed from 18 to 37 seats and just over 18 per cent of the popular vote. That is up noticeably from the years under his predecessor, Alexa McDonough, but still behind the 44 seats the party won with Ed Broadbent at the helm in 1988.

In his personal battle with cancer, and his political battle to become prime minister, the common factor has been his determination.