KEY POINTS:
Influential right-wing radio hosts are openly alarmed at the likelihood of John McCain winning the race to become the Republican presidential candidate.
Leading host Rush Limbaugh said McCain spelled danger for the party on ideological grounds, and callers to his show deplored his "liberal" views, saying he lacked the bedrock convictions of former President Ronald Reagan, a Republican hero.
Their fears present a stiff challenge to McCain's efforts to unify Republicans along conservative lines.
The Arizona senator won nine coast-to-coast primary races on "Super Tuesday" and now Mitt Romney has withdrawn is the most likely candidate to secure the party's nomination.
"We are trying to stop the wanton destruction of the party, the wanton dilution of the party," said Limbaugh, whose daily show is syndicated on radio stations across the country.
"We are sick and tired of how the people who seem to be triumphing in our party are precisely the people who seem to be selling this party out in terms of its ideology," said Limbaugh, who criticised McCain for reaching out to Democrats.
Conservatives say they disagree with McCain on issues including taxes, free political speech, immigration and the treatment of prisoners at Guantanamo Bay and other prisons.
In one indication of doubts about McCain, evangelical leader James Dobson said this week he would not vote for McCain if he became the nominee, raising the possibility that some Republicans would sit out the November election.
Limbaugh's views on McCain reflect wider disquiet that George W. Bush and Republicans have squandered years in power by failing to institute principles such as individual freedom and small government or to sufficiently write Christian values into law.
They say a McCain presidency would likely move the party further in the wrong direction.
At the same time, many conservatives are angry at what they see as a biased national media that applauds McCain for "moderate" views, relishes division within Republican ranks and misrepresents the influence of talk radio.
Limbaugh is credited with fuelling the rise of AM talk radio in the United States and opening the way for popular talk show hosts.
Another host, Sean Hannity, said McCain might move to the left if he won the nomination to try to pick up centrist votes.
"The problem [with] John McCain ... isn't that he's a moderate Republican. It's worse than that on some issues and that's just a substantive disagreement," he said.
Some see Limbaugh, Hannity and others as extremists servicing an embittered, though powerful, minority. Some commentators say McCain's rise shows Republicans are moving left and the influence of talk show hosts is waning.
Syndicated talk radio host Neal Boortz, who describes himself as a libertarian, said conservatives should be realistic and recognise that no candidate matched their views.
"I am ... curious about those Republicans ... who are insisting on 100 per cent purity in their presidential candidate. That's not going to happen," said Boortz, who backs Mike Huckabee.
- REUTERS
