In 1998, as citizens of Arizona were preparing to vote on Proposition 300, pundits became concerned that voters did not understand the issue. A poll was subsequently fielded by the Survey Research Laboratory at Northern Arizona University (#15). It questioned whether voters were likely to vote "yes" or "no" on the upcoming initiative, with "no" favoring medicinal cannabis. The poll correctly predicted the winning margin of 57%, and the "no" vote restored to physicians the right to prescribe marijuana and other Schedule I drugs under state law.

After passage of the Arizona initiative, citizens were again asked in May of 1999 (#27) whether they favored or opposed Federal sanctions against doctors who prescribe medical marijuana, such as license revocation. The percentage opposed – favorable to medical marijuana – had risen to 66%.

Survey questions that asked specifically about upcoming ballot initiatives were also fielded in Colorado (#34), Nevada (#33 and #16), and Oregon (#18), returning respective favorable percentages of 67%, 63%, 52%, and 59%. Each of these polls foretold its initiative’s success with the respective voting percentages of 54%, 65%, 59%, and 55%, showing that polls taken prior to medicinal cannabis ballot initiatives successfully predict their passage every time.