I have had FIVE calls from this number during the past week. Apparently whoever is calling doesn't want to leave a message on the answering machine. This most recent time, I was actually present when the phone rang. The caller ID indicated, "Heritage 2." I picked up the phone and gave a polite hello, and there was no response. I hung up.
Most likely a scam fundraiser claiming to be for Heritage. I am a member of the Heritage Foundation, and they call me directly, rather than using any paid fundraiser.