Yes, they certainly can subpoena any citizen to testify before Congress. They can also cite people for contempt of Congress if they lie or refuse to answer questions. Remember the “Hollywood Ten”?
I don't think either House of Congress has tried to directly hold anyone in contempt since the 1930s. The modern practice is for the House (or Senate) to ask the US Attorney for Washington DC to go to US District Court in DC and ask a Judge to hold the person in contempt.
Since both the US Attorney, and the Federal Marshals, work for Attorney General Holder, I wouldn't hold my breath for that to happen.