Rasmussen Reports conducted a survey in Colorado at the end of November, gathering data on head to head match-ups. The match-ups were related to the Senate race between Schaffer and Udall, as well as head to head presidential preferences in a Rudy/Clinton, Huckabee/Clinton, Romney/Clinton, McCain Clinton match-up.
Schaffer leads Udall in the senate race, 42% to 41%.
Rudy Beats Hillary: 44% - 40%
McCain Beats Clinton: 44% - 40%
Huckabee Beats Clinton: 42% - 41%
Romney Loses to Clinton: 40% - 43%
Remember, it all comes down to picking up electoral votes in the general election. Who is REALLY electable? Look at which states they stand to lose or gain from the 2004 electoral map.
From Colorado's standpoint, Rudy, McCain, and Huckabee stand to hold Colorado, while Romney would deliver Colorado to Clinton.
If there are any more state head-to-heads, please let me know. I would like to build an electoral map based off these head to head match-ups.