PlayUS Republicans are standing by their vice-presidential nominee Sarah Palin after she revealed her daughter is pregnant.
John McCain's running-mate, a staunchly conservative and anti-abortion Alaskan governor, said 17-year-old Bristol will keep the baby and marry the father.
"Our beautiful daughter Bristol came to us with news that as parents we knew would make her grow up faster than we had ever planned," said the Palins in a brief statement.
"We're proud of Bristol's decision to have her baby and even prouder to become grandparents."
Democratic politicians joined their Republican rivals in calling on the public and media to respect the privacy of Mrs Palin's family.
Mr McCain's spokesman Steve Schmidt said: "Senator McCain's view is this is a private family matter. As parents, the Palins love their daughter unconditionally and are going to support their daughter. Leave the kids alone."
Democratic Presidential nominee Barack Obama also called for restraint.
He said: "I have said before and I will repeat again, I think people's families are off limits and people's children are especially off limits.
"This shouldn't be part of our politics. It has no relevance to Governor Palin's performance as a governor or her potential performance as a Vice-President.
"So I would strongly urge people to back off these kinds of stories. You know, my mother had me when she was 18. And you know, how family deals with issues and teenage children - that shouldn't be the topic of our politics."
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