There are still four Republican presidential hopefuls in the race for the White House. But front-runner Mitt Romney is increasingly seen as the inevitable winner.

Now the former Massachusetts governor is turning his attention to November and sharpening his attacks against President Obama.

"We just gotta get him out of office. He just doesn't understand what's happening in the country," said Romney, who is campaigning in Pennsylvania ahead of the state's primary on April 24.

Romney and the president have zeroed in on each other, both appearing eager for direct engagement.

Romney accused the president of disguising his intentions.     

"He wants us to re-elect him so we can find out what he will actually do with all the challenges the nation faces," Romney said. "This is not the time for President Obama's hide-and-seek campaign."

The Obama campaign responded by launching an ad challenging Romney's claims against the president.

"I believe deeply that the free market is the greatest force for economic progress in human history," Obama says in the spot.    

GOP Budget

The GOP budget proposal is also turning into a campaign issue. In a speech earlier this week, Obama attacked the plan and its author, Rep. Paul Ryan, R-Wis., labeling it a Trojan horse.

"Disguised as deficit reduction plan, it's really an attempt to impose a radical vision on our country," Obama claimed.

Romney commended Ryan for having the courage to offer serious solutions to the country's skyrocketing deficit spending.

The latest polls show Romney trailing Obama nationally, with more women supporting the president.