Our client fell victim to the act. She had been passing through a parking lot of an Illinois shopping mall and was approached by a voting booth representative. Asked if she is registered to vote, our client stated she is not a US citizen. The representative asked if she is married to a US citizen, and if so, she is able to vote due to that status.
A K-1 fiancé(e) visa allows you to enter the US, and it buys you some time (90 days, to be exact) to stabilize your immigration status. Marrying your US citizen partner, however, is not the end of the story -- you are still going to need to change your status to permanent resident in order to remain in the US long-term.