Yes, a Voter Participation Center mailer inviting you to use a QR code to take a survey is legitimate: VERIFY
The mailer includes suspicious hallmarks of scams, but it's actually not a threat, so it's safe to take the survey, if you want to.
How To Make The Most Of A QR Code In A Multichannel Marketing Strategy
After declining in popularity for a time, QR codes are back, offering a seamless bridge between physical and digital ...