This is what I was looking for.
I find myself in those situations quite often when I make it deep in a tourney.
BTW, When you have to push and your first in vigorish, what would be your lowest pushing range from EP, MP, LP?
Harrington on Hold'em Volume 2 covers this nicely. I recommend reading Harrington on Hold'em Volume 1 and Volume 2 as they'll do a better job explaining than I will.
With an M of 5, assuming nobody has VP$IP'd into the pot, at a full table...
Early on I'll shove T/J+, 8/9s+, and any pair.
On the button I'll shove any two cards if the blinds are short too. Otherwise, any Face/rag, any pair, any connectors.
Of course, the situation varies depending on the likelihood of being called. People with middle stacks will be hurt pretty badly if they call my shove, and they are comfy with their stacks, so they are far less likely to call if I shove. People with an M of 2 or so are apt to call with anything, as are big stacks, so I shove against their blinds with a tighter range.
How active I've been (my image) and how eager to call the field has been will also effect that range.
One thing Harrington says in the book that stuck with me was that shoving with an M of 5 and winning gets you a stack of chips that have potential. So even if you're 40% to win, it's worth taking that risk for them. 40% isn't all bad, and you win that a significant number of times. If you fold a couple rounds and are down to an M of 2.5, well, even if you go in as a 60% favorite and win you only get back to an M of 5 which is still desperate/shove-and-pray time.