http://www.iowafirstcaucus.org/pdfs/2008_Caucus_Guide.pdfHere's the information I think you want for your friend:
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11) Caucuses that elect only one county convention delegate:
If there is only one county convention delegate to elect, the delegate will be
elected by the caucus as a whole by majority rule. The caucus will not divide into
preference groups. Written ballots MUST be used. Note: All ballots must be
signed
Skip to item 29.
12) Caucuses that elect two or more county convention delegates:
The Chair will determine whether the caucus attendees wish to divide into
preference groups. When more than 15% of the caucus attendees wish to
divide, then the caucus will divide into preference groups. If more than 85% of
the caucus attendees do not wish to divide, then the delegates shall be elected
by the caucus as a whole.
If your caucus does not divide into preference groups, skip to item 29.
13) Now the Chair will determine the viability threshold that a preference group must
attain in order to be considered viable.
The Chair will count the number of eligible voting caucus attendees and
announce the number to the caucus.
Reminder: An eligible caucus attendee is:
· A resident of Iowa and of the precinct in which they wish to participate.
· A U.S. citizen and otherwise eligible voter (18 by November 4, 2008).
· A registered voter, registered as a Democrat (they can register at the
caucus).
· In line or signed in by 7:00pm.
Note: This process may not begin until 7:00pm
14) After the number of eligible caucus attendees has been determined, the viability
threshold is calculated based on the number of delegates the caucus is to elect.
Note: When calculating viability, always round UP to the next whole number.
a. In caucuses that elect two (2) delegates, preference groups must contain at
least 25% of the caucus attendees in order to be viable. This can be
calculated by using the following formula:
Number of Eligible Caucus Attendees x 0.25 = Viability Threshold
b. In caucuses that elect three (3) delegates, the total caucus attendees should
be divided by six (6) to determine the viability threshold. This can be
calculated by using the following formula:
Number of Eligible Caucus Attendees (divided by)6 = Viability Threshold
c. In caucuses that elect four (4) or more delegates, preference groups must
contain at least 15% of the caucus attendees in order to be viable. This can
be calculated by using the following formula:
Number of Eligible Caucus Attendees x 0.15 = Viability Threshold 15) Once the viability threshold has been determined, the Chair will announce that
number to the caucus.
Note: The viability threshold remains unchanged throughout the course of the
caucus, even if attendees leave before delegates are awarded.
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It was always easier for the media to report the 15% viability threshold than explain that there were several levels to the threshold. This is the way viability has been determined since the 1970's. It is nothing new.
Hope this helps.