U.S. Sen. Tom Udall is seeking his second term, and with a sizeable campaign fund, the Democrat has been trying to fend off Republican challenger Allen Weh.
A businessman and retired Marine colonel, Weh has trimmed Udall's lead. His campaign is airing commercials linking Udall with unpopular leadership in Washington, D.C., saying a vote for Udall amounts to support for President Barack Obama's failed policies.
New Mexico's three congressional seats are also up for grabs.
In southern New Mexico, Republican incumbent Steve Pearce is fighting off attacks from national Democrats and challenger Roxanne Lara.
In the 1st District, Democrat incumbent Michelle Lujan Grisham is facing Republican Mike Frese, a scientist and small business owner.
Democrat incumbent Ben Ray Lujan and Republican Jeff Byrd are vying for the 3rd District seat.
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