Groups That Need The Career Making Song

In a comment on Daniel Mount’s post about the Collingsworth Family’s latest single, an interesting question is brought up about groups that may be top notch groups that have not had that one song that puts them “on the map” or “over the top”, so to speak.  Think Gold City and “Midnight Cry”, the Cathedrals and “Champion of Love”, the Nelons and “Oh For A Thousand Tongues”, etc.  Of course, off the top of my head I came up with the obvious new groups that are poised to do so:  the aforementioned Collingsworth Family, the Dills, the Crist Family, the Ball Brothers, Tribute Quartet, and so on.  Then my brain went into overdrive and I came up with two well established and wildly popular groups who still fit the above criteria:

• Legacy 5
• Triumphant Quartet

As popular as these two groups are, and as talented as they are (two of my favorites, even), I still can’t point to the one “monster” song that has defined their career.  Legacy 5′s closest is probably their debut single, “I Stand Redeemed”, but it still isn’t the “signature song” that “Midnight Cry”, “When He Was On The Cross”, or “Get Away Jordan” has been.  With Triumphant it is even harder, though “Don’t Let The Sandals Fool Ya” was and is pretty popular for them.  What do YOU think?  And who would you add to the list of groups that still haven’t had that one smash of a song that is a line in the sand and a measuring stick for all others?