I've always wondered what the delegate count is based upon?

Below is the Republican delegate allocation. I'll just give the link to the Democratic allocation. The Green Papers web site contains one of the best resources I've found for info on present and past Presidential elections....

Delegate Allocation

Republican Delegate Allocation. (Reference Rule 13 of "The Rules of the Republican Party")

For Jurisdictions with Constitutionally Elected Members of Congress:
- 10 At-Large delegates from each state, that is, 5 at-large delegates for each U.S. Senator.
- 3 District delegates for each U.S. Representative.
For Jurisdictions without Constitutionally Elected Members of Congress:
- 6 at-large delegates from American Samoa.
- 16 at-large delegates from the District of Columbia.
- 6 at-large delegates from Guam.
- 6 at-large delegates from the Northern Mariana Islands.
- 20 at-large delegates from Puerto Rico.
- 6 at-large delegates from Virgin Islands.
For all Jurisdictions - 3 party leaders: the national committeeman, the national committee woman, and the chairman of the state Republican Party.
Bonus Delegates
- 2004 Bonus: States casting a majority of their 2004 Electoral Votes for the Republican Candidate receive 4.5 + 0.60 × the Jurisdiction's Total 2004 Electoral Vote bonus delegates. Should the District of Columbia cast the majority of their electoral votes for the Republican Candidate, the District will receive 4.5 + (0.30 × 16) bonus delegates. (Round any fractions UP to the next integer.)
- U.S. Senate: Award 1 bonus delegate for each Republican Senator elected in the 6 year period (November 5, 2002, November 2, 2004, November 7, 2006) prior to January 1, 2008. (Limit 2)
- Governor States electing a Republican Governor between January 1, 2004 and December 31, 2007 receive 1 bonus delegate. (Limit: 1)
- U.S. House: States electing Republicans to 50% or more of the their U.S. House seats between January 1, 2004 and December 31, 2007 receive 1 bonus delegate. (Limit 1)
- One Chamber: States electing a Republican majority to one chamber of the state legislature (OR the legislature is presided over by a Republican) receive 1 bonus delegate. (Limit 1).
- All Chambers: States electing a Republican majority to all chambers of the state legislature (or all chambers are presided over by a Republican) between January 1, 2004 and December 31, 2007 receive 1 bonus delegate. (Limit 1).

Democratic allocations

The Green Papers