King County Elections has posted an announcement on its home page about the GOP trying to collect ballots, and saying, basically, don't give them your ballot. "We recommend that voters return ballots to an official King County Elections ballot drop-off location or through the US Postal Service," the website advises. In other words, don't trust the GOP.
County elections spokeswoman Kim van Ekstrom explains they found out about the GOP trying to collect ballots after they received "a call to our phone bank, and we want voters to know we are aware of this activity." Thanks to Janis for the tip.