Over the years, I have gotten some tshirts from presidential campaigns.

Clinton/Gore 92

Kerry/Edwards 04

Obama/Biden 08

Obama/Biden 12

Biden/Harris 20

Harris/Walz 24

So, let's have a little experiment. 

92: got shirt, Yes; candidate won, Yes

96: got shirt, No; candidate won, Yes

00: got shirt, No; candidate won, No

04: got shirt, Yes, candidate won, No

08: got shirt, Yes, candidate won, Yes

12: got shirt, Yes, candidate won, Yes

16: got shirt, No, candidate won, No

20: got shirt, Yes, candidate won, Yes

24: got shirt, Yes, candidate won, ?

So, over the last 8 elections, this is the tally: 

Got shirt, candidate won: 4 (92, 08, 12, 20)

Got shirt, candidate lost: 1 (04)

No shirt, candidate won: 1 (96)

No shirt, candidate lost: 2 (00, 16)

So, to summarize: 

of the times I got a shirt, the candidate won 80% of the time

of the times I did not get a shirt, the candidate lost 66% of the time.

Make of this what you will...

POLT