He didn't reprise his famous scream, but the man who engineered the Democratic party's return to power in the U.S. Congress shared his winning strategy as the Liberal party opened its convention Wednesday night.

Howard Dean urged Liberals to court all voters, even in areas traditionally held by their opponents.

Howard Dean outlines how his Democratic Party in the United States rebuilt itself.

"Whether it is the Liberal party or the Democratic party, we should never cede a single region or a province, never cede a single state or a city, never cede a single voter, not a single one," the chair of the Democratic National Committee said during the convention's keynote speech in Montreal.

"It is a mark of respect for the voters that we ask every single one for their vote, regardless of the likelihood of getting it."

The former Vermont governor was referring to his "50-state strategy," which he said played a key role in the recent U.S. mid-term elections that gave his party control of the both the House of Representatives and the Senate.

The strategy sent vital DNC funds to boost the party's local organizations in states such as Alaska and Mississippi, which are not traditionally viewed as winnable for Democratic candidates.

Dean said they went into places that hadn't voted Democrat or even "seen a Democrat in some time."

"Show up everywhere, work hard everywhere, knock on doors everywhere, make the calls everywhere, shake hands everywhere, do the hard word everywhere and keep doing it every day because that's what running a permanent campaign is all about," Dean advised Liberals. 

But the strategy came under fire from some high-profile Democrats, who said the money would have been better spent in critical swing races that determined the balance of power in the election.

Dean is perhaps best known for his on-stage scream during the Democratic primary races in 2004.

"I am certain I could scream," Dean joked. "But don't worry, I won't do so.

"Let me say I learned my lesson the hard way."

Dean's role as keynote speaker had rankled some Liberals, who were upset that an American had been chosen to speak at their national convention.