BOSTON — Gov. Deval Patrick has signed a prayer canvas that organizers hope will act as a message of support on the anniversary of the Boston Marathon bombing.

Supporters said the America 4 Boston Prayer Canvas has been signed by more than 70,000 people from 50 states and 30 nations.

The 19,000-square-foot canvas was started by seven women in Florida a week after the bombing.

They started with a single canvas asking people to sign their name and write a message.

The canvas is set to be displayed at several events around the anniversary of the attack.

On April 16-17 the canvases will be laid out on the Boston Common. Members of the public can sign it.

Patrick put his signature on the canvas during a brief ceremony at the Statehouse on Friday.