Research 2000 is out with a new poll in Iowa. For the Democrats, Hillary Clinton and Barack Obama have lost ground since the last Research 2000 poll while John Edwards has not:

Democrats
Edwards 27 (+1 vs last poll May 14-16)
Clinton 22 (-6)
Obama 16 (-6)
Richardson 11 (+4)
Undecided 16 (+6)

Edwards leads by 1.8% in the latest RCP Average for Iowa.

On the Republican side, Mitt Romney surges into a strong lead while Thompson continues to rise and Giuliani and McCain slide:

Republicans
Romney 25 (+9 vs last poll May 14-16)
F. Thompson 14 (+5)
Giuliani 13 (-4)
McCain 10 (-8)
Gingrich 6 (nc)
Undecided 22 (nc)

Mitt Romney currently leads by 9.0% in the latest RCP Average for Iowa.

General Election Match Ups
Clinton 42 - McCain 36
Clinton 41 - Giuliani 37
Clinton 42 - Romney 34
Clinton 41 - Thompson 31

Edwards 43 - McCain 36
Edwards 43 - Giuliani 36
Edwards 45 - Romney 34
Edwards 45 - Thompson 28

Obama 44 - McCain 36
Obama 45 - Giuliani 36
Obama 44 - Romney 34
Obama 43 - Thompson 29

Other notables: President Bush's job approval is at 27% - including only 55% among Republicans. Only 24% said going to war with Iraq was worth it. A striking 45% approve of Congress beginning impeachment proceedings against the President (74% D, 8% R, and 24% I) while 46% oppose the idea. And a majority, 54%, approve of Congress beginning impeachment proceedings against the Vice President (81% D, 14% R, and 63% I), while 40% oppose and 6% are unsure.

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