Senate Majority Leader Harry ReidHarry ReidDems face identity crisis Heller under siege, even before healthcare Charles Koch thanks Harry Reid for helping his book sales MORE (D-Nev.) trails two potential Republican opponents in a new independent poll testing those matchups.

Reid trails real estate businessman Danny Tarkanian and Nevada GOP Chairwoman Sue Lowden in a Mason-Dixon poll conducted this past week and released Sunday.

Tarkanian, a former basketball player for the University of Nevada - Los Vegas, would take the support of 49 percent of Nevadans, while 38 percent would support Reid for reelection. 13 percent of Nevada voters were undecided between the two choices.

By contrast, Lowden would beat Reid 45-40 percent, with 15 percent undecided.

National Republicans have made targeting Reid a priority in their 2010 midterm election efforts. And while the polls show Reid below the 50 percent threshold considered healthy for incumbents, Reid's been furiously raising money for the race, reporting a hefty $7.3 million in cash on hand through the end of June, in Federal Election Commission (FEC) filings.

Republicans also haven't been able to draw their preferred candidates into the race, either. Nevada Lt. Gov. Brian Krolicki (R) had been a favorite recruit until falling under ethical scrutiny, and Rep. Dean HellerDean HellerKoch-backed group launches new ads on tax reform Overnight Healthcare: GOP infighting erupts over bill | How Republican governors could bring down ObamaCare repeal | Schumer asks Trump to meet with Dems GOP infighting erupts over healthcare bill MORE (R-Nev.) had declined to challenge Reid in recent weeks.

(Mason-Dixon tested a potential Heller-Reid race. 50 percent of Nevada voters said they would support Heller, and 40 percent would support Reid, with the rest undecided.)

National Democrats and Republicans have made a point of targeting Senate leaders in their reelection efforts this past decade. Republicans managed to knock off then-Senate Minority Leader Tom Daschle (D-S.D.) in 2004, while Democrats almost succeeded in unseating Senate Minority Leader Mitch McConnellMitch McConnellValerie Jarrett slams GOP for not including women in healthcare discussions Healthcare wish lists: What moderates, conservatives want Top GOP lawmaker questions tax break for wealthy in healthcare plan MORE (R-Ky.) in 2008.

The poll, conducted August 17-18, has a five percent margin of error.