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The Republican contest to hold onto the seat of retiring New Mexico Sen. Pete Domenici still has three weeks to go before the primary vote, but already Reps. Heather Wilson and Steve Pearce have struck a contentious note, with a rash of negative TV ads earlier this month. That tone looks unlikely to change after Wilson began airing an ad this weekend criticizing Pearce for votes to shutter a local Air Force base and cut funding to government labs such as the one at Los Alamos.

"Pearce voted four times to slash lab funding that would have cost New Mexico thousands of jobs and put America's security at risk," the ad (subscription) warns. "Heather Wilson fought for New Mexico every time." Most of the attacks traded by the two campaigns in their paid media have revolved around their respective voting records in Congress.

The ad is Wilson's second of the race. Like her first, it concludes by labeling her a "common-sense conservative" -- setting her up as a more pragmatic, centrist alternative to Pearce, whose advertising has emphasized his ideological purity, calling him the "one conservative running for Senate."