SERGEANT BLUFF, Iowa — In the final days before the Iowa caucuses, Republican presidential hopeful Mitt Romney has launched aggressive ads against rivals John McCain and Mike Huckabee. But on the campaign trail, he’s using a different weapon: his wife Ann.

The loyal political spouse, gazing lovingly at her husband, is as much a fixture of American politics as giant stars-and-stripes backdrops. Democratic hopeful Barack Obama’s wife, Michelle, has featured prominently in his campaign stops and former president Bill Clinton has stumped extensively to help his wife Hillary Clinton’s White House bid.

But in the final leg of Romney campaign before the Jan. 3 Iowa caucuses, it’s sometimes seems unclear whether Ann or Mitt has top billing.

In campaign stops on Friday and Saturday, Anne spoke nearly as long has her husband, discussing her battle with multiple sclerosis and the difficulty of raising five boys.

While Romney’s sharp-edged ads filled the airwaves, his wife praised him as a devoted father and husband, drawing an implicit contrast to rivals like former New York mayor Rudy Giuliani whose personal lives have not been so squeaky clean.

 ”When I’ve had troubles and difficulties, he’s been right behind me, and right beside me,” she said, fleshing out one of Romney’s major themes: the importance of family.

“There’s no work in America that’s more important to our future than the work that goes on in the four walls of the American home,” candidate Romney said in Sioux Center on Friday.

But some stories carry a darker undercurrent, illustrating the toll that ambition can take on family life. Ann says that when her multiple sclerosis was at its worst in the 1990s, Mitt decided to move the family from Boston to Salt Lake City to run the Olympics.  

Mitt notes that he spent much of  his business career on the road, leaving her alone to raise their five rambunctious boys. But even these tales are woven back in to the campaign’s family-friendly message.

Mitt would call home to encourage Ann over the phone during that period, both said. “He told me that what I was doing was more important than what he was doing, that what I was doing was more lasting than what he was doing, and to hang in there,” Ann said.

– Photo credit: Reuters/John Gress