Who called from 7402171236

This is extended auto warranty company. Lady was very rude when I told her I wasn't interested.

Call log:
Caller ID;
17402171236
Patriot OH
Date/Time Jul 24, 2015 12:02 PM EDT
Caller did not press required numbers to complete the call.
Probable Robodialer.

Based on the caller ID, probable political pest.

Didn't leave a message.

Answered, no response. When I called back it asked if I wanted removed from their list.

lady called and I asked how she got my number. She said from national registry. As soon as she knew I already had a car warranty, she hung up. How do they get my number? I am on a do not call list?