I distinctly recall when Ace of Spades flipped from being suspicious of Obama's birth to complete intolerance of any discussion regarding it. Prior to the discovery of those Newspaper announcements in those two Hawaiian newspapers, Ace was supporting questions about Obama's origins, and refusal to release a birth certificate. As soon as those announcements were discovered, not only Ace flipped, but so did Drew, Gabe, Monty, Maetenlock, Dave, and the entire gang at Ace of Spades. Ed Morrisey and Allahpundit (Hot Air) were already against any inquiry into the issue, but with the Crew at Ace of Spades, it was like a light switch. I could SEE the Cascade and Herd mentality taking effect. They went from asking the same questions, to rabidly opposing any further inquiry. From there it spread throughout most of the Conservative movement with Eric Erickson of "Red State" viciously banning any and all discussion of the topic.
I have long thought that one of the major reasons for this is the belief that inquiries into whether Obama was born in America were regarded as dangerous to the Republican Candidate John McCain who was definitely NOT born in the United States. Discussing the issue was seen as DANGEROUS to our side politically. The MOST vicious vituperative verbal assaults I ever received in any of these discussions were for suggesting that these people were motivated by "pragmatism". That's how I knew I had struck a nerve.
So in a word, Yes. I do think most conservatives made up their minds too early (cascade) and "herded up" to oppose the dissenters which they regarded as political threats. As time went on their positions just only grew more rigid. The "Conspiracy" word was repeated often with rolled eyes in an effort to demean and discredit those remaining dissenters, but despite that, the meme was spreading that Obama was somehow illegitimate. It is still spreading, but at a much lower rate now that he's released his image file which is supposed to be a copy of his original birth certificate.
At this point it appears that the election will come and render the whole discussion moot. For what it's worth, I believe most of the Anti-birthers here at Free Republic are more likely to be RNC establishment types than DNC trolls. Not all, but most.
As long as we are clear that you see the evaluation of conclusive evidence as just following the herd.