How is Membership Campaign computed?

I'm getting different numbers for a query with V_MEMBERSHIP_CURRENT/TX_CONT_MEMB/T_CONTRIBUTION than using the Campaign/Campaign element in Analytics.  For the primary campaign I'm looking at I get:

Query: 1136 (or 1050 without Lapsed)

Analytics: 975 (no filters applied)

Of the three other, much smaller, campaigns, two are one membership higher by query, and one (the smallest) is the same as Analytics.