Rasmussen's latest nationl poll confirmed earlier numbers which seemed to indicate an upward trend for Romney. The latest has him ahead of McCain for the first time in any national survey.
From the survey report :
The immigration reform debate may be shaking up the race for the Republican Presidential nomination. Former Massachusetts Governor Mitt Romney has inched past Arizona Senator John McCain for second place in the latest Rasmussen Reports national telephone poll. Just two weeks ago, Romney was in fourth place among GOP hopefuls.
Former New York City Mayor Rudy Giuliani (R) remains on top with 25% support. That's essentially unchanged from last week . In fact, Giuliani has been at 25% or 26% in the polls for four straight weeks.
This week, Giuliani is followed by Romney at 16%, McCain at 15%, and former Tennessee Senator Fred Thompson at 12%. While Romney's one-point edge over McCain is statistically insignificant, it's worth noting that McCain had a six-point advantage over Romney just two weeks  ago.
Hmmm. What big national news have the candidates made in the past few weeks that has the capability to move potential GOP primary voters??? Can you say "immigration"? I knew that you could.