As Ron Paul's 2012 campaign continues to gain steam - he and Mitt Romney are essentially tied for first place in Iowa - attacks from his Republican rivals have gotten nastier.

Mitt Romney is painting Paul as a fringe candidate.

Romney told RealClearPolitics that Paul is not going to be our [i.e. the Republican Party's] nominee. He said Paul does not represent the mainstream, reported The Associated Press.

ABC News found clips of Newt Gingrich claiming there is no chance Paul would be elected, Rick Santorum declaring Paul is the least likely to beat Obama and Jon Huntsman opining that Paul is not electable.

(Paul, however, has consistently polled ahead of Huntsman and Santorum. Moreover, he consistently polls well in head-to-head matchups against President Obama).

ABC also found clips of Rick Perry, Michele Bachmann and Romney attacking Paul for his noninterventionist position on Iran.

On Fox News, Santorum called Paul's foreign policy stance dangerous and in the Dennis Kucinich wing of the Democratic Party.

In his zeal to attack Paul, Gingrich even brought up the decade-old newsletters that Paul has repeatedly denied writing or even reading. In an interview with CNN, the former House Speaker urged Americans to read the newsletters and look at what [Paul] said.

Perhaps the strangest attack against Paul comes from Bachmann.

On Wednesday, her Iowa campaign chairman Ken Sorenson defected to Paul's camp. In his defection statement, Sorenson said he still maintained respect for Bachmann but wanted to give his support to Paul partly because of Paul's top-tier status.

Bachmann, however, immediately accused Sorenson of switching sides because he was offered money by Paul's campaign.

Eric Woolson, Bachmann's Iowa campaign manager, backs up her account.

Sorenson himself denies Bachmann's allegation, as does Wes Enos, Bachmann's own Iowa political director at the time.

Interestingly, a Bachmann staffer said Enos no longer works for the campaign just hours after Enos came to Sorenson's defense, according to CNN.

I've been saddened by the way Congresswoman Bachmann's campaign has decided to handle my decision to endorse Ron Paul for President of the United State, said Sorenson in a statement.