So you can't hum a tune on a message board - And you only know 1 or 2 lines of lyrics

[Maynard]

It's 25 or 6 to 4, by Chicago. Great tune. I recommend getting their First Greatest hits album Chicago Greatest Hits. Amazing album. It has 25 or 6 to 4, Colour My World, Does Anybody Really Know What Time It Is, Saturday In The Park, and many more. It's a great album.