One sign was the nomination of Oliver North to carry the Republican flag against the incumbent Senator, Charles Robb, in Virginia. It is the home state of the evangelist and one-time presidential candidate, Pat Robertson, whose followers played a big role in propelling the Iran-Contra villain turned populist to victory at last weekend's convention.
Barring upsets, the next 10 days will bring two further triumphs for the religious right and deepen the fissures laid bare by Colonel North. In disciplined, liberal Minnesota, the moderate sitting Governor, Arne Carlson, is about to be disowned by the party convention in favour of an anti-homosexual, anti-abortion conservative, Allen Quist, who claims that men have a 'genetic predisposition' to be heads of household. Mr Carlson's waning hopes of re-election depend on Minnesota's nominating primary in November.
This weekend in Texas, meanwhile, right-wingers who have forced out the veteran Republican chairman, Fred Meyer, are expected to have one of their own elected to head the party's organisation in the third largest US state. Moderates fear the step will damage the chances of George Bush, son of the former president, defeating Governor Ann Richards in November, and even scotch the re- election of Kay Bailey Hutchinson, the golden girl of Senate Republicans in Washington.
For some, like the Republican analyst Kevin Phillips, the alarm is exaggerated. 'There are 15 or 20 states,' he says, 'where the religious right either once controlled, does control, or could control the local party - but never all 15 or 20 at the same time.' Even so, the inroads are undeniable and, as the continuing North controversy shows, the intra-party turmoil ever more obvious.
This week, the Senate minority leader, Bob Dole, the party's senior spokesman, expressed his displeasure at Colonel North's success and hinted he might follow the example of Virginia's Republican Senator, John Warner, and back an independent Republican against Colonel North. Within 24 hours, Mr Dole came under fire from leading conservatives.
The advance of the religious right is almost a mirror image of the 'entryism' tactics by which the far left made inroads into the British Labour Party in the 1970s. In the US, committed activists with fundamentalist views pack the grass-roots meetings that pick delegates to important bodies. Church-linked parish assemblies, often so influential in rural America, speed the process.
Today, according to a recent study, the religious right has effectively seized control of Republican organisations in Texas, Oregon, Iowa, Virginia, South Carolina and Washington state. In California, New York, Florida and Louisiana it has made notable gains. Whether the successes are to the party's overall benefit is debatable.
They pose a similar dilemma to Republicans as the Labour entryists 20 years ago. The party cannot afford to alienate its most committed and energetic supporters, of priceless fund-raising powers. But too much obvious influence for the fundamentalist Christian right risks alienating the swing voters who decide elections.
President Bush's difficulties in 1992 stemmed in part from a Houston nominating convention that adopted a platform outlawing abortion, and came across on television as a prime-time rampage by intolerant zealots, pounding more reasonable voices into silence. The same, some party strategists fear, could happen this autumn, when Republicans hope to pick up some 20 House and at least four Senate seats. The party may have more difficulty picking a centrist candidate who could upset a vulnerable President Clinton in 1996.
Mr Clinton has lost no time in exploiting the opportunity. Hardly had Colonel North been chosen than the President called it a victory for the 'radical right', which was trying to take over 'first the Republican party and second this country'.