A new series of polls of presidential matchups between announced and potential Republican presidential candidates by Rasmussen shows that other candidates are showing momentum against Barack Obama besides former Massachusetts Governor Mitt Romney, the frontrunner in the race currently.

Romney beats Obama 43%-42% in the poll, and this win is probably because he is currently perceived as the frontrunner for the Republican nomination. Obama leads New Jersey Governor Chris Christie, who has repeatedly said he wouldn’t run, 44%-37%. Obama leads Texas Governor Rick Perry, who is very likely to run, 44%-39%.

Obama leads Minnesota Rep. Michele Bachmann 46%-39%, and she is in second in most recent polls for the Republican nomination. Obama leads former House speaker Newt Gingrich 48%-30%, whic isn’t a surprise considering how Gingrich’s campaign is failing. Obama leads Texas Rep. Ron Paul 41%-37%. That poll is very surprising, giving the libertarian-leaning congressman some momentum going into the Ames Straw Poll.

Obama leads former Minnesota Governor Tim Pawlenty 44%-32%, which is a bigger lead than usual over TPaw. Obama leads businessman Herman Cain 49%-28%, a very large lead and possibly a blow to Cain’s campaign. Obama leads former Utah Governor and former US Ambassador to China under President Obama Jon Huntsman, Jr. 44%-28%, performing better than Cain, which is weird.

Former Pennsylvania Senator Rick Santorum loses to Obama 45%-31%. Obama leads former New York City Mayor Rudy Giuliani 44%-39%, which helps him because he hasn’t announced a campaign yet. Obama leads former Alaska Governor Sarah Palin 47%-39%, which is better than usual for the unannouncie.

(Credit to Rasmussen for the info)