Mason-Dixon is out with a new 2008 poll in Nevada. The big news from the poll comes on the Republican side, where Fred Thompson has surged into the lead and John McCain has fallen from first to fourth:

Republicans
Thompson 25 (+12 vs. last poll 4/30-5/2)
Romney 20 (+5)
Giuliani 17 (+5)
McCain 8 (-11)
Huckabee 3 (+2)
Undecided 23 (-5)

It should be noted that the new poll did not include Newt Gingrich, who garnered 7% support in the April 30-May 2.

On the Democratic side, Hillary Clinton maintains a strong lead over Barack Obama:

Democrats
Clinton 39 ( +2 change vs. last poll 4/30-5/2)
Obama 17 (+5)
Edwards 12 (-1)
Richardson 7 (+1)
Undecided 21 (+2)

Again, it's worth noting that the new poll did not include Al Gore while the last poll did, with Gore receiving 9% support. (CLARIFICATION: In the new Mason-Dixon poll, Gore did get 1%, but that support was "volunteered" by respondents. His name was not among the list of candidates offered by Mason-Dixon this time around.)

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