Major Premise: An “extremist” is a person whose views are very far removed from the mainstream; they are not merely a strong adherence to a common opinion, but the holding of opinions that are in themselves very unusual.
**Minor Premise: ** Taken as a whole, popularly elected members of congress reflect the general spread of opinion in the United States; with the exception that extremists (of all stripes) are rarely represented. Politicians as a group, IOW, have a general bias toward the center.
Conclusion: Anyone who can win support from a majority of congresspeople is, almost by definition, not an extremist.
And of course, you can see where this is headed.
Let’s put this in hypothetical terms: let us assume that on Bizarro-earth, President Kerry is attempting to put a nominee through the senate, which the Democrats control by a 55-45 margin. Now the Republicans would understandably prefer that he nominate a true moderate; say a Harold Ford. But Kerry, knowing the composition of congress, sends up Barney Frank. Rep. Frank is indisputably distasteful to the hard right; he also would easily win confirmation in the senate I posited above, and I submit that nearly by virtue of that alone he could not be called an “extremist.”
The evidence of that is that were a true extremist – let us say Cynthia McKinney or Dennis Kucinich – nominated, they would likely not pass the senate; centrist democrats would begin deserting. Despite remors to the contrary, politicans of neither party vote in 100% pure partisan lockstep; they are keenly aware that they are being watched by their constituients, and that confirming, for partisan reasons, someone that a large majority of their supporters think is a kook is not good for their own political health.
Thus, my conclusion: if someone is really and truly an “extremist” – i.e. far, far removed from the mainstream of public opinion – it should be fairly easy to convince a few members of the other party of that. If one cannot, that person is demonstrably not a extremist.