Yeah, and they'll all put on "Don't blame me, I voted for an obscure 3rd party candidate" after President Kerry loses the first city to a nuke. If the election of 2000 didn't demonstrate that EVERY vote counts, then nothing will. Get each state to switch over from winner takes all electoral votes to a scheme like Maine's or Nebraska's where the winner in each congressional district gets that electoral vote (and the winner of the popular vote gets the two "senatorial" votes) and THEN your 3rd party vote would count for something. The time for "sending a message" to the Republican party is over - that was the primary. In the general election, a Constitution party vote (other than in ME and NE) is as good as a vote for Kerry. Sorry, but that is reality in 2004.
Sorry but your analysis does not hold water.
In non-battleground states, such as New York or California, a principled conservative can certainly vote for the Constitution Pary or Libertarian party candidate without affecting the outcome of the election. You can be sure that the Republicans and Democrats watch the inroads that 3rd party candidates make on their margins of victory.
In battleground states, its even more critical that they win. In these cases, its up to each individual voter how they will vote. Will they vote with their head held high, or will they vote with their fingers pinching their noses.
The primary is an infomercial and the candidate is already picked by powerful party insiders before the door opens.
Protest outside, and get beaten and arrested.
This leaves only one effective method for conveying a message...