The dramatic resurgence of Republican fortunes since 2008 may be developing into an electoral steamroller in time for midterm elections. Most observers expect Democrats to lose most of their margin in the House and Senate. President Obama will definitely have to deal with Senate filibusters and a much more fiscally conservative House.

At the state level, things look equally grim for Democrats. Even in true-blue California, Republican fortunes look good, with very credible candidates for both governor and senator. But move just one level lower, and the Achilles heel in the Republican electoral juggernaut comes into sharp relief.

The candidate is Orly Taitz, a dentist and night-school lawyer who has become the leader of the “birthers” — conspiracy theorists who contend that President Obama was actually born in Kenya and who somehow forged a Hawaii birth certificate to obtain eligibility to run for the Presidency. If Taitz wins today’s primary, she will be the Republican candidate for Secretary of State in California. She will also be a millstone around the neck of the much more credible Republican candidates for other state offices.

Taitz is the personification of the nuttiest wing of American politics. Alongside the “truthers” (who believe that 9/11 was an inside job by the Bush administration), “birthers” represent what has been called the “paranoid style in American politics”. In fact, “birthers” and “truthers” share a surprisingly large proportion of membership in spite of the supposedly right-wing orientation of “birthers” and supposedly left-wing orientation of “truthers”.

Taitz has taken her particular brand on the road, filing lawsuits on behalf of military officers (sometimes without their permission) seeking to cancel deployment orders (sometimes the very orders they requested in order to concoct grounds for a lawsuit) on the basis that President Obama is not legitimately commander-in-chief. Taitz’ legal efforts have been a spectacular failure, with one (politically conservative) judge openly mocking her allegations and eventually tagging her with tens of thousands of dollars in fines as punishment for repeated violations of court rules.

Taitz legal arguments also can’t even be dignified with with term “specious”. There exists no legal right for military officers to require their superiors verify eligibility to give orders before those officers are obligated to follow orders. Imagine the spectacle of every superior officer up to and including the President to have to present papers proving their proper birth and proper commissioning to each and every subordinate as a prelude for each and every order. Yet Taitz is clueless or, perhaps, so obsessed so as to not care.

The trouble for Republicans is that Taitz represents a movement that is powerful and fed by ignorance and resentment. Just like some on the left were willing to wink at the “truthers” as an indulgence of their hatred towards Bush, some within the highly energized “tea party” movement are willing to pay footsie with the “birthers” as an indulgence in their hatred towards Obama. In this way, Taitz may be Republicans’ version of Cindy Sheehan (also from California, who has previously threatened a primary challenge against House Speaker Nancy Pelosi because of Pelosi’s lack of progressive purity…seriously) — an energizing figure that everyone knows is a total loon, but which one side is too emotionally sympathetic towards to condemn publicly. As a result, that loon’s political influence grows vastly out of proportion to her level of sanity.

And the distorting effects on the broader message are very dangerous. Sheehan’s antics were great fun for the loony left, but to the broader public they were a constant drain on credibility. Democratic candidates were forced simultaneously to pretend to honor her stature while distancing themselves from her proclamations of support for Hugo Chavez and Fidel Castro, her condemnations of capitalism, and her other far-left talking points recycled from 40-year-old protest movements. With Taitz, Republican candidates in 2010 could be forced into the same awkward bind, having to flirt with expressions of respect for her highly energized supporters while condemning her excesses and all the while dealing with a media and blogosphere eager to find a storyline to link them to Taitz personally.

Once again, California is revealing itself as the insane asylum of American politics.