Presumptive Republican presidential nominee Mitt Romney is sharpening his focus on the November general election, as he tries to convince voters he is a better choice to lead the country than President Barack Obama.

Five states hold Republican primaries Tuesday, but with his top challenger out of the race, Romney will be elsewhere, holding an event in New Hampshire that aides say will mark a transition away from the nominating contest. He is expected to win all five contests.

His campaign has been attacking the president's policies, issuing statements Monday criticizing Mr. Obama's work on health care and energy, and asking what he has done for young people since taking office.

Mr. Obama, a Democrat, begins a two-day trip Tuesday touting his plans for more affordable higher education with stops at college campuses in the key electoral states of North Carolina, Iowa and Colorado.

The president wants Congress to extend a law set to expire in July that would prevent interest rates on student loans from doubling.

Romney also endorsed the plan Monday during a stop in Pennsylvania, one of the states holding primaries Tuesday. The others are New York, Connecticut, Delaware and Rhode Island.

Romney won New Hampshire in January, his first victory of the 2012 Republican nominating contests. He has not yet reached the 1,144 delegates needed to become the party nominee, but remains far ahead of the other two candidates, who have little chance of overcoming him.

Rival Rick Santorum dropped out of the race two weeks ago. His exit leaves former House speaker Newt Gingrich and Texas Representative Ron Paul as the only remaining Republican challengers.