Colorado law outlines how a petition may be circulated. House Bill 09-1326, signed into law on May 15, 2009, establishes additional requirements for petition circulators.
There are two ways to place an issue on the ballot.
"The procedures for placing an issue or question on the ballot by a petition of the electors of a county that is pursuant to statute or the state constitution or that a board of county commissioners may refer to a vote of the electors pursuant to statute or the state constitution shall, to the extent no such procedures are prescribed by statute, charter, or the state constitution, follow as nearly as practicable the procedures for municipal initiatives and referred measures under part 1 of article 11 of title 31, C.R.S. The county clerk and recorder shall resolve any questions about the applicability of the procedures in part 1 of article 11 of title 31, C.R.S." [30-11-103.5 C.R.S.]
The full text of the Colorado statutes concerning petitions is available at www.michie.com/colorado. The relevant sections are under Colorado Revised Statutes, Title 31, Article 11.
The petition process involves months of preparation prior to the election. The following is an abridged version of steps one can expect to encounter to place an issue on the ballot. This is not a substitute for legal advice and the full text of Colorado law.