It is pretty easy to get an 80 in 2008 when one is only there for 9 of 25 votes:
[+] 01. Earmark Disclosure S1 (Roll Call 5).
[+] 02. Regulation of Grassroots Lobbying S 1 (Roll Call 17).
[X] 03. Iraq WarCloture S 574 (Roll Call 51).
[+] 04. Tax Cuts SConRes 21 (Roll Call 107).
[+] 05. Alternative Minimum Tax SConRes 21 (Roll Call 108).
[+] 06. Estate (Death) Tax Repeal SConRes 21 (Roll Call 109).
[-] 07. Stem Cell Research S5 (Roll Call 127).
[X] 08. Small Business Regulation S 761 (Roll Call 139).
[-] 09. Immigration OverhaulCloture S 1348 (Roll Call 206).
[X] 10. Coastal Drilling for Natural Gas HR 6 (Roll Call 212).
[X] 11. Energy Policy HR 6 (Roll Call 226).
[+] 12. Employee RightsCloture HR 800 (Roll Call 227).
[+] 13. Social Security Benefits for Illegal Aliens HR 2669 (Roll Call 263).
[X] 14. New Student Loan Program S 1642 (Roll Call 273).
[X] 15. U.N. Peacekeeping Operations HR 2764 (Roll Call 317).
[X] 16. Abortion and Sterilization HR 2764 (Roll Call 318).
[X] 17. Mexico City Policy HR 2764 (Roll Call 319).
[X] 18. Davis-Bacon Requirement HR 3074 (Roll Call 334).
[+] 19. District of Columbia Congressional SeatCloture S 1257 (Roll Call 339).
[X] 20. Hate CrimesCloture HR 1585 (Roll Call 350).
[X] 21. Health Insurance Expansion HR 976 (Roll Call 353).
[X] 22. Energy PolicyCloture HR 6 (Roll Call 425).
[X] 23. Eminent Domain HR 2419 (Roll Call 429).
[X] 24. Energy Policy HR 6 (Roll Call 430).
[X] 25. Alternative Minimum Tax Adjustment HR 2764 (Roll Call 440). ACU: 2007 US Senate Votes
Of the 9 votes he made, he voted sideways on two. And look at the two he was bad on:
[-] 07. Stem Cell Research S5 (Roll Call 127).
[-] 09. Immigration OverhaulCloture S 1348 (Roll Call 206).
If one counts his missed votes against him, He voted ACU Conservative only 7 of 25 times.
That would be a rating of only 28%.
Here's his bad votes in 2006:
[-] 04. Tax Cut Rules S Con Res 83 (Roll Call 38)
[-] 12. Immigration OverhaulSocial Security Credit S 2611 (Roll Call 130)
[-] 14. Immigration Reform S 2611 (Roll Call 157)
[-] 15. Same-Sex Marriage Ban Constitutional Amendment S J Res. 1 (Roll Call 163)
[-] 17. Native Hawaiian Government S 147 (Roll Call 165)
[-] 18. Iran Sanctions S 2766 (Roll Call 172)
[-] 22. Border Fencing HR 5441 (Roll Call 200)
[-] 23. Embryonic Stem Cell Research HR 810 (Roll Call 206)
Then lets look at his bad votes in 2005:
[-] 02. Tax Cuts -- Fiscal 2006 Budget Resolution. S Con Res 18 (Roll Call 59)
[-] 08. Climate Change -- Energy Policy. HR 6 (Roll Call 148)
[-] 13. Mercury Emissions Rule -- Passage. S J Res 20 (Roll Call 225)
[-] 17. ANWR Oil and Gas Leasing -- Budget Reconciliation. S 1932 (Roll Call 288)
[-] 20. Tax Increases on Oil and Gas Development -- Tax Relief Act of 2005. S 2020 (Roll Call 332)
I see you and I had similar analysis. I count 10 votes, though. See my post above.