A key figure on the US religious right, which is anxious that its political grip on the large evangelical constituency in America is waning, has launched an attack on Senator Barack Obama and his Christian credentials.
Mr Obama, who has just received full backing from former president Bill Clinton, came under fire yesterday from James C. Dobson, founder of the ultra-conservative Focus on the Family organisation.
Dobson accused the likely Democratic nominee of "twisting the Bible" to confuse people, but his speech was high on rhetoric and selective, observers said.
The attack from Dobson, a leading figure of the Christian Right, was framed as a wholesale rejection of the Democrat's views on faith, and appeared to be an anxious response to Obama's success in reaching out to many evangelical Christians, especially the younger generation.
The overtly partsian comments were delivered in Dobson's regular radio programme as a line-by-line dissection of a speech that Obama gave to a progressive Christian organisation two years ago on the role of religion in public life.
Dobson's organisation also emailed links to the programme out to news organisations, demonstrating that the attack was a concerted effort.
"I think he is dragging biblical understanding through the gutter," said Mr Dobson. "I just don't know whether he is doing it deliberately or accidentally."
The Focus on the Family leader had pointedly refused to sign a recent manifesto from mainstream evangelicals calling for an end to partisanship and political posturing in the name of faith.
The attack on Obama comes at a time when some established evangelical leaders - especially those on the right like Dobson - are confronting the waning of their influence over American politics.
However, religion remains a potent force in American life. More than 90% of Americans believe in God and more than half pray at least once a day, according to a study this week by the Pew Forum on Religion and Public Life.
The evangelical community has grown disillusioned with the performance of George Bush, who failed to live up to their expectations as a born-again president. Evangelicals are also unenthusiastic about the coming elections.
Dobson has said he will not vote for Republican John McCain in November 2008 because "he is not a true conservative."
"This is a year when we have a lot of frustration with the major political parties," he declared.
Barack Obama and other Democrats have been working hard since 2004 to win over a younger and more open generation of evangelical voters through Christian radio programmes, meetings, discussions and blogs.
Critics have said that the so-called "moral majority" claimed by the US religious right "is now neither moral nor a majority".