He was elected MP for the seat of St Albans in England, in 1640. In fact he was elected twice in the same year, firstly for the Short Parliament the a few months later for the Long Parliament. This is all on record, I can't see how the same man could have died five years earlier in America.
See: http://books.google.co.uk/books?id=5V09AAAAYAAJ&pg=RA2-PA229&am...
Look down the list for the county of Hertford - St. Albans - John Jennings Knight of the Bath .