MITT ROMNEY cruised to primary victories in Pennsylvania and four other Northeastern states Tuesday against a shrunken field of challengers, cementing his status as the presumed Republican nominee against President Obama in the fall.

Romney sought to frame the contest as a referendum on whether Americans are better off than they were four years ago, arguing that most are not, in a prime-time speech in New Hampshire.

Most of the remaining drama drained from the GOP presidential race two weeks ago, after Rick Santorum dropped his campaign, concerned that he was headed for a loss in Pennsylvania, the state he had represented for 16 years in the House and then in the Senate.

Santorum grew up in Pennsylvania, and two other candidates still in the race were born in the state - former House Speaker Newt Gingrich (Harrisburg) and libertarian-minded Texas U.S. Rep. Ron Paul (Pittsburgh).

Gingrich, his campaign nearly broke, concentrated his efforts in Delaware, which was to award all 17 delegates to the winner. He had said that he would "reassess" his campaign if he did not do well there, and Romney was way ahead of him late Tuesday night.

Paul told CNBC Tuesday that he would press on to the convention, seeking to have as many delegates as possible. "You don't quit because you happen to be behind," he said. "And who knows? Maybe somebody will stumble."