Rumors abound on the campaign trail today that a big Iowa voice is set to endorse John Edwards. His campaign is mum, but Democratic sources in Iowa believe that Mari Culver, the wife of Gov. Chet Culver (D), is set to endorse the former North Carolina senator tomorrow.

The governor himself is said to be remaining neutral, but if his wife endorses Edwards, the larger Culver orbit will be seen to have descended on Edwards's campaign. (Mari Culver endorsed Edwards in 2004).

Gov. Culver's chief of staff, Patrick Dillon, worked for Edwards in Iowa in 2004, and his is married to Jennifer O'Malley, Edwards's state director. Another Edwards alum serves as Culver's communications director.

In 2004, Gov. Tom Vilsack's wife, Christie Vilsack, endorsed Sen. John Kerry at a critical moment late in the primaries. Vilsack ostensibly remained neutral.

New Hampshire Gov. John Lynch hasn't endorsed, but his wife has -- Hillary Clinton.

Four Edwards spokespersons declined to comment, and a spokesman for Culver did not return an e-mail request seeking comment.