US Senator Hillary Clinton, favorite Democratic candidate in the presidential race, was joined in her campaign by former US president, husband Bill Clinton.

Presidential hopeful Hillary Clinton and former president Bill Clinton made their first joint public campaign appearance since Hillary Clinton announced her candidacy in January.

The two emerged on a three-day tour of Iowa, where both talked to the welcoming crowds, with Bill introducing his wife with short biographical speeches. So far, Hillary’s campaign team has kept her husband in the shadow, with the spotlight on her own achievements and political beliefs.

Bill Clinton introduced Hillary to the crowds in Iowa City with warm words “When I first met Hillary I told her ... she had the best combination of mind and heart. Thirty-five years later I am more convinced of it.”

“I'd be here tonight, if she asked me, if we weren't married,” he told an audience Monday night.

Bill played the role of supportive husband easily, telling an audience: “We sort of changed roles now. I'm kind of out of politics and I'm a little rusty, so you'll have to forgive me.”

Hillary has many faithful supporters who wish to see her at the White House. She leads national polls but she trails rival John Edwards, the party's 2004 vice presidential nominee, in Iowa. Iowa holds the first presidential test vote in January 2008.

As to fundraising, she trails rival Barack Obama, the Illinois senator, with Obama reporting an unprecedented record-breaking second quarter contributions.