Public Policy Polling (PDF). 4/19-22. New Mexico voters. MoE ±4.3% (6.0% for Democratic primary sample) (12/10-12/2011 in parentheses):
Martin Heinrich (D): 48 (47)
Heather Wilson (R): 43 (40)
Undecided: 9 (13)
Hector Balderas (D): 44 (43)
Heather Wilson (R): 43 (43)
Undecided: 12 (14)
Martin Heinrich (D): 51 (47)
Hector Balderas (D): 27 (30)
Undecided: 22 (23)
No news is probably good news in the New Mexico Senate race, where Public Policy Polling finds Democratic Rep. Martin Heinrich is maintaining a mid-single-digit lead over Republican ex-Rep. Heather Wilson in the likeliest November matchup. Heinrich's lead is slightly smaller than their previous sample from last December, but the change is well within the margin of error and, maybe more notably, he's edged closer to the 50 percent mark, at 48.
It's a little surprising that Wilson is keeping it as close as she is, given New Mexico's increasingly blue hue (Barack Obama has lead in the low double-digits here in most polls, leaving New Mexico looking like the least swingy of the swing states). She's faring as well as she is because of a fair amount of Democratic crossover, picking up the votes of 16 percent of Dems (while losing only 4 percent of Republicans). What's keeping her from doing better, though, is independents; she's down 40-37 among indies to Heinrich, but New Mexico's registration is Dem-tilting enough that any Republican has to clean up among indies to hope to win statewide. (PPP found Susana Martinez up 60-34 among indies right before she won in 2010, for instance.)
Republicans have seemed optimistic about this race, often including it on their list of top pickups potentials, and making a huge ad reservation for the fall here already, which means they're gambling big on it staying competitive. However, the problem here for Wilson is that she seems close to maxed out on potential support. Most people already know her, as seen in her 40/45 favorables, and she's already locked down the Republican vote (with 73/15 faves among them). Heinrich has more upside at 34/31 favorables overall, and 55/16 faves among Democrats, leaving him much more room to grow.
The general election race gets closer if state Auditor Hector Balderas wins the Democratic primary. As you can see from the primary portion of the poll, though, that's looking less likely (especially considering that Heinrich just started advertising on TV this week, and with a weak fundraising first quarter, Balderas seems unlikely to be able to respond). Balderas and Heinrich are tied at 40% apiece for Hispanic support in the primary, but he'll need to totally dominate that segment to win.