With the economy and the Keystone XL pipeline in the balance, the 2012 battle for the hearts and minds of Americans will have major ramifications for Canadians. With this in mind, we take a look back at some of most powerful and persuasive American political ads.

10. Shame On You (2012 Romney)

This recent ad by the Romney campaign questions the credibility of Barack Obama's attacks by flashing voters back to the 2008 Democratic primary, when Hilary Clinton railed against Barack Obama for "perpetuating falsehoods."

9. The Bear (1984 Reagan)

At first glance, one might think this ad was paid for by the nature channel, but using the bear to represent Soviet Union reminded Americans of the Cold War's modern threat.

8. Daisy (1964 Johnson)

This ad only aired once but media reports replaying the ad ensured millions of voters saw it. A girl counting flower deals helped scare away enough voters away from Republican Barry Goldwater to secure Lyndon Johnson a second term.

7. Willie Horton (1988 National Security PAC)

Americans and Canadians continue to be outraged when they see gross examples of our justice systems playing nice with violent offenders. This powerful ad by the National Security political action committee played into voters' basic morality and assisted the Bush campaign's assertions that Dukakis was weak.

6. How're You Doin? (1992 Clinton)

Going into the 1992 campaign, no one gave Arkansas Governor Bill Clinton much hope against a Gulf War triumphant George Bush. But by changing the narrative to Americans' concerns for the economy (and with help from Ross Perot), the Clinton team was able to take back the White House after twelve years of Republican rule.

5. Dukakis on a tank (1988 Bush)

The image of Michael Dukakis looking awkward riding a tank again played into the Republican narrative that Dukakis wasn't tough enough to be the leader of the free world.

4. Celebrity (2008 McCain)

With Obama's popularity soaring to unparalleled heights, the only way the McCain campaign could bring him back to earth was to try to pop his celebrity balloon. Featuring Paris Hilton, it was an effective ad in an otherwise gaffe-prone campaign.

3. Troubled (2012 Obama)

The always controversial topic of abortion has reared its head once again in this year's race, as the Obama campaign tries to strike fear into pro-choice women.

2. Next Century (1996 Clinton)

Reminiscent of our top political ad, Clinton's 1996 campaign narrative was one of achievement and better days ahead. This ad helped Clinton assure voters that he was the right man to lead America into the 21st century.

1. Morning in America (1984 Reagan)

With Americans tired of Jimmy Carter's malaise and worried about their future, they elected Ronald Reagan and his conservative vision in 1980. Four years later, Americans were feeling better about their country and Reagan used this narrative to crush his Democratic challenger, Walter Mondale. Emotionally charged and compelling, political ad makers from around the world have tried to recreate Morning in America's brilliance.