Washington Marijuana Legalization Measure at 55%Phillip Smith The 55.4% support figure includes 48.7% who are certain yes voters, 4.3% who are yes could change, and 2.8% who are undecided leaning yes. The 37.6% no figure includes 35.5% certain no voters, 1.6% no could change, and 0.5% who are undecided leaning no. Some 6.8% of voters remained truly undecided, while 0.3% said they would not vote on I-502. One-third (33.4%) of those surveyed have already voted, the poll found. Pollsters surveyed 722 registered voters between October 18 and 31. The poll has a margin of error of +/- 3.6%. linkwithin_text=Related Articles: 