There are some songs that get me pretty much every time.
Elbow have a habit of knocking me for six, mainly when live, but sometimes just listening at home.
Lippy Kids - the first "Nobody knew me at hoooooooome anymore"
The Birds - the first "Do they keep those final kisses / in their tiny racing hearts"
Mirrorball - only when played live. This was our first dance, which exacerbates the emotion now.
Think with those three, it’s the sentiment of the lyrics mixed with Elbow being like a massive hug, multiplied by being one of the few bands the TV really loves.
Sufjan is another who has the capacity to bowl me over, normally by delivering a starkly emotive line amidst the poetry of his lyrics. On reflection, it appears to be whenever he talks about love.
John My Beloved - "I love you more than the world can contain / In its lonely and ramshackle head"
Futile Devices - "And I would say I love you / But saying it out loud is hard / So I won’t say it at all"
The Predatory Wasp of the Palisades Is Out to Get Us! - “We were in Love! We were in Love!”
The other one which springs to mind is June Hymn by The Decemberists. This was true before it was the bridal entrance music at our wedding, and is even worse now. Dear Avery hits me hard as well actually, come to think.