Republican incumbent: Pete Domenici (not seeking reelection)
Democratic candidate: U.S. Representative Thomas Udall
Republican candidate: U.S. Representative Stevan Pearce
Udall, 60, has represented New Mexico in the House since 1999. He had previously been that state's attorney general. His father, Stewart Udall, also served in Congress, and was Secretary of the Interior in the Kennedy and Johnson administrations. His uncle, the late Representative Morris Udall, ran unsuccessfully for president in 1976.
Pearce, 60, has been in the House since 2003. He previously served in the state legislature.
Polls cited by Real Clear Politics show Udall leading by margins ranging between 17 and 28 points.
Here is an article describing Udall's huge fundraising edge.
A Udall victory would be a major reverse for the Republicans. Domenici has been elected to the Senate six times, with wide margins of victory in the last four of those races. But without the advantages of incumbency, the Republicans will have a difficult time holding on to this seat in a state where the Democrats have shown significant strength in recent years.