Mitt Romney scores primary hat-trick as he steps up campaign Mr Romney's victories in Wisconsin, Maryland and Washington DC will stretch further an already commanding lead in delegates over his nearest opponent, former Pennsylvania senator Rick Santorum. According to the Associated Press, Mr Romney looked on course to secure at least three-quarters of the 98 delegates on offer tonight, putting him at 646 to Mr Santorum's 272. While Mr Romney is only just over half way to the 1,144 needed to secure the nomination he needs to win less than half of the remaining delegates - a rate of victory that should be well within his grasp. The exchange of fire between the Republican frontrunner and the Democrat president left Mr Santorum struggling to make himself heard as he begged conservative voters to reject Mr Romney, who he called the choice of the party's "establishment and aristocracy." He compared his electoral situation to that of Ronald Reagan's in 1976, when the conservative icon languished in the early contests against President Gerald Ford before winning a string of conservative states like Texas. Inconveniently for Mr Santorum's analogy, Reagan went on to ultimately lose to the nomination. "There's one person [Reagan] who understood we don't win by moving to the middle, we win by getting people in the middle to move to us to move this country forward," Mr Santorum said in defiance of conventional logic that dictates Mr Romney's appeal to independents and moderates makes him a stronger general election candidate. Close observers of Mr Romney's candidacy also noted that he was introduced onstage by Congressman Paul Ryan, a young darling of the conservative movement, who many political analysts believe is at the top of the frontrunner's list of potential running mates.