Liberal MP Marc Garneau has officially pulled himself out of the party's leadership race and thrown his support behind front-runner Justin Trudeau.

Despite running a ''solid second'' in the federal Liberal leadership race, Garneau made the decision after internal polling made it clear to that winning would be impossible given Trudeau's lead.

He says he'll continue to be a loyal Liberal soldier.

The decision leaves seven candidates in the running.

Garneau, an MP since 2008, kicked off his campaign last November, stressing the economy as his key issue.  He has spent the last few weeks trying to take the fight to Trudeau, but his efforts haven't had much measurable impact.

Voting will be conducted online and by phone early next month, with the winner to be announced on April 14.