Stage Two: Days Mentioned
I have been stabbed, shot, poisoned, frozen, hung, electrocuted, and burned.
Electrocution we saw, see it's up there in the list - but the other six account for an additional six days (again assuming they weren't on the same day). Which brings the running total up to 44 days.
But then that isn't factoring the number of days of perpetuation that it would take to force a man who is already thoroughly depressed to attempt suicide - delicate matter, but since Phil is an entirely self-centred man, trapped in his own idea of hell, and surrounded by "hicks", you'd have to wager that normal circumstances wouldn't apply. If it were me, a month would be more than enough time to drive me to despair, and I'd say Phil Connors was at least as self-aware as I am, if not more given that he gives up "living by their rules" on day 3 - so let's factor in 20 more days at this point. That's 64 days so far.
And then there's the scene where Connors tells Rita exactly how long it would take to learn how to expertly throw playing cards into an upturned hat:
"Six months. Four to five hours a day, and you'd be an expert."
So, that's 6 months added to the 62 days, bringing the running total to 244 days (taking a month as 30 days).
The insightful quotes don't stop there- next up is the scene in which Phil takes a companion in a French Maid outfit to see Heidi 2 at the local cinema, and teasingly says:
"It's like I said: I love this film. I've seen it over 100 times."
There's another 100 days then - seriously, who would see the same film twice in the same day? Especially when its Heidi 2... New total so far: 344 days Add to that two full days of Jeopardy watching to be able to perfectly recite the answers (spread over some other days no doubt - but probably empty days, considering Phil's mood at that point in the movie) and you have 346 days.
Then of course there's the diner scene in which Phil explains to Rita that he is stuck reliving Groundhog Day, and uses his extensive knowledge of the other diners to prove his point - let's give each person a day (ignoring Nancy, as she's in the original 38 on-screen days), since he clearly knows a lot about them. So that's a day each for Doris the waitress, Debbie and Fred, Phil the waiter, Gus the drunk ex-sailor, Tom the former coal miner and Alice the waitress, totalling 6 additional days, bringing us to 352 days.
And finally, in this section are the few odd bits and pieces mentioned on screen that would have taken some time, including sourcing a Rolls Royce and Cowboy outfit in small-town Punxsutawney and meeting his French maid companion, discovering the candy store, finding out that Rita likes Rocky Road, and generally learning everything there is to know about Rita.
Conservatively, that's going to be 100 extra days, most of which would be spent in Phil's attempts to find out as much about Rita as possible to give her the perfect date. Keeping up? We're on 452 days already. Next up, the number of days Phil takes to learn things...