Iowahawk skewers the better class of Republicans in his T. Coddington Van Voorhees VII pieces.
Snoop around the links I provided. Start here:
Elected members of the Republican Main Street Partnership
37 House members, 5 listed SINators and 2 governors are on their elected members list. Prior to the '06 election, there were 5 governors and there were more than 45 House members, IIRC. I firmly believe they have at least 5 alternate SINators that are not listed. If you watch their votes, I think you will see 10 that change off voting with the demonRATS.
Also, there were 21 SINators listed in the 107th Senate Centrist Coalition, during President Bush's first 2 years in office. By the 109th the group had been drastically reduced. I guess they thought they had effectively neutered President Bush and could simply use that damage to effect the '06 election. There was also a House Centrist Coalition, but I can no longer find info about them.
However, there is The Centrist Coalition.
The first National Centrist Meeting was held in the Theodore Roosevelt Birthplace Home in New York on May 6, 2006. It would appear they took the place of the of the so-called Centrist Coalitions in both Houses.
Check out their favorites under the "Candidates" link.
Also note, where ever you find the word "centrist" there will you also find the name, McCain.
Another very interesting web site:
Radical Middle.