More than half the pork stays in = House wins.
Less than half the port stays in = Senate wins.
50/50 = draw.
No budget and House leaves = Senate wins.
Why? Because the Senate intends to exert itself as an equal player on the budget. They don’t get to originate it, but they can make it their own. The House intends to make it clear that it is in charge of the budget. Too much give and the House concedes otherwise.
UPDATED: Icarus makes a good point in the comments:
Governor calls special session = Governor wins. Of course, given how much the Governor and House have been in sync over the budget, if that happens without strong Senate PR first it becomes:
Special Session w/o Senate PR = Casey loses.