To win the Superbowl you need to score more points than the other team. There is a multitude of ways to go about doing that involving either scoring a lot oneself, being able to prevent the other team from scoring a lot, or if a team is lucky being good at both.
However, considering teams like the Patriots, Packers, Saints, and Indy before they collapsed it's very viable to win any game with a lousy defense when you can score a lot. The whole defense winning championships things is just a saying and only one viable solution.
Whoa, buddy let's take a second to look at the stats and data before we go around just spitting out "facts.. So let's take a look at the last 20 super bowls:
1993: Dallas Cowboys: defensive rank = 5
1994: Dallas Cowboys: defensive rank = 2
1995: San Francisco 49ers: defensive rank = 6
1996: Dallas Cowboys: defensive rank = 3
1997: Green Bay Packers: defensive rank = 1
1998: Denver Broncos: defensive rank = 7
1999: Denver Broncos: defensive rank = 9
2000: St. Louis Rams: defensive rank = 4
2001: Baltimore Ravens: defensive rank = 1
2002: New England Patriots: defensive rank = 6
2003: Tampa Bay: defensive rank = 1
2004: New England: defensive rank = 1
2005: New England: defensive rank = 2
2006: Pittsburgh Steelers: defensive rank = 4
2007: Indianapolis Colts: defensive rank = 23
2008: New York Giants: defensive rank = 17
2009: Pittsburgh Steelers: defensive rank = 1
2010: New Orleans Saints: defensive rank = 20
2011: Green Bay Packers: 2
2012: New York Giants: 25
So, in the past 20 years 16 out of the 20 super bowl winners had a defense that finished in the top 10. So, yes sometimes a good offense or a match up can single handily win a super bowl, but most of the time you need a pretty good defense. So the good old saying comes in : Offense wins the regular season, defense wins championships. But almost always you need a good defense and offense. So please, do some research next time. :google: