Doctors for the Jewish congresswoman critically wounded during a shooting rampage at an Arizona supermarket have said there are signs she could recover.

Six people were killed, including her political aide Gabe Zimmerman, and 13 others injured in the attack on Saturday in Tuscon.

The man suspected of being behind the shooting spree, Jared Loughner, will appear in court today on several charges including attempting to assassinate Gabrielle Giffords.

The 40 –year-old, shot in the head at close range, is still in intensive care but her medical ream has said she has responded to signals.

Mr Loughner, 22, is believed to have named Mein Kampf as one of his favourite books and been in trouble with the police before this.

Described by those who know him as an outcast, he has had contact with Ms Giffords a number of times before. Police said an envelope with Ms Giifford’s name and the phrases “my assassination” and "I planned ahead" written on it had been found, with what appeared to be his signature beside it.

The authorities are also looking into suspected links with a white supremacist, anti-immigrant group, the American Renaissance.

Considered a rising star in the Democratic Party, Ms Giffords is the southern state’s first Jewish representative.

The attack comes just days after she was sworn in for her third term, taking the oath of office on a copy of the Old Testament.

The granddaughter of a Lithuanian rabbi, she has a non-Jewish mother but chose to follow her father’s religion by visiting Israel and attending Reform services .