While many in the Liberal Party are welcoming MP Marc Garneau鈥檚 entry in the federal leadership campaign, some are saying the greatest challenge to the former astronaut鈥檚 campaign is the perception that he鈥檚 simply a 鈥渂ack-up鈥 to frontrunner Justin Trudeau.

CTV's political analyst Scott Reid says there鈥檚 already a feeling among political observers that while Garneau is a very strong candidate, he simply can鈥檛 compare with Trudeau. In a column Wednesday, the Toronto Star鈥檚 Chantal Hebert went so far as to call Garneau 鈥渁n insurance plan鈥 for the Liberal Party.

鈥淢eaning, if Mr. Trudeau should blow himself up over the course of this race, isn鈥檛 it great that you鈥檝e got Mr. Garneau -- a person who鈥檚 solid, who鈥檚 experienced, who鈥檚 well-respected -- sitting in the wings,鈥 Reid explained to CTV鈥檚 Canada AM Thursday.

鈥淭he harsh reality is that people don鈥檛 expect Marc Garneau to win; they鈥檙e just happy he鈥檚 in the race.鈥

Reid says a lot of Liberals wanted Garneau to join the race not because they necessarily plan to support him, but so they can say that the campaign included lots of strong contenders and wasn鈥檛 just a coronation for Trudeau.

With the Liberals in third place and perhaps on the brink of collapse, Reid says the party badly needs a charismatic leader who can turn the party around.

鈥淭he hard question for a lot of Liberals is: Can they afford to look at a gift like Justin Trudeau 鈥 a guy with charisma who sparks genuine enthusiasm and a popular reaction 鈥 can they look at that in the mouth and say, 鈥榥o thanks,鈥 鈥 Reid said.

鈥淚 think if you鈥檙e in the process of trying to save your party, a guy who animates genuine interest like Justin Trudeau is probably someone the party is going to be hard-pressed to pass up.鈥

Garneau, 63, see things a little differently himself.

He told Canada AM that the reason he鈥檚 running for the leadership is because he believes he鈥檚 the best candidate for the job.

鈥淚 think the main question when Liberals vote next April is who can defeat Stephen Harper, and that鈥檚 based not only on your ideas, but on your track record and leadership qualities,鈥 Garneau said.

鈥淚鈥檓 very glad that Justin is in the race as well, as well as the other candidates. It will allow Liberals to hear from a range of people and see what they have to say,鈥 he added.

Garneau said he鈥檚 running because he believes that most Canadians have different values than Stephen Harper and that Harper is not doing a good job on the economy.

He said he understands well how important the oilsands and the resource economy are to Canadians -- particularly those in the West; he himself was on the board of directors of an oilsands company for two years and is now the Liberals鈥 natural resources critic.

But he says if Canada is going to weather the next global economic storm, it needs an economy that鈥檚 less reliant on one key industry.

鈥淲e are very blessed in this country to have wonderful natural resources and we should develop them. But what Harper is not doing is developing the knowledge-based economy, and we have a great deal of potential for that in this country,鈥 Garneau said. 鈥淲e have a well-educated and talented workforce and he鈥檚 put all our eggs in one basket by pushing natural resources.鈥

Garneau, a father of four, was elected to the House of Commons in 2008 after a high-flying career as an astronaut, becoming the first Canadian to fly in space, in October 1984.

He then became executive vice-president of the Canadian Space Agency in 2001, and later president of the organization. He left that position in 2005 to pursue politics.

Three MPs 鈥 Garneau, Trudeau, and Joyce Murray 鈥 have now thrown their hats into the leadership race.

The other candidates for the job include former MP Martha Hall Findlay, Toronto lawyer Deborah Coyne, Vancouver prosecutor Alex Burton, Ottawa lawyer David Bertschi, retired Canadian Forces Lt.-Col. Karen McCrimmon and David Merner, former president of the Liberal party's British Columbia wing. George Takach, a Toronto technology lawyer, is also joining the race, declaring his candidacy Thursday.

The Liberals will choose a successor to interim leader Bob Rae on April 14, 2013.