“She [Mrs. Bush] was reminding me of the Kenny Rogers song, ‘There is a time when to hold them, a time when to fold them’. Well I think it is time for people to all get behind this good man,” he said.

Romney has what appears to be an insurmountable lead in the delegate count for the Republican nomination and is eager to get the primary race behind him.

“And I think it is important for us to select a nominee and to get on with a campaign that will focus on two very different visions for America,” said Romney.

But rivals Newt Gingrich, Ron Paul and Rick Santorum are pressing on in the hope that Romney falters.

"I think the American people are tired of politicians who will tell you whatever you want to hear when they are in front of you and then go and do what is politically expedient," said Rick Santorum.

Among those Republicans anxious for the primary race to end is Representative Steve Chabot of Ohio.

“As a Republican myself I would like to see a lot of that firepower that is directed at each other directed at the president’s policies," said Chabot in a VOA interview. "Let’s have the American people focus on what he has done right or done wrong.”

The Republican candidates attacking each other could help President Obama in November, says Quinnipiac pollster Peter Brown.

“And that kind of negative tone rubs off and politics is the ultimate zero-sum game," he said. "What is bad for the Republicans is good for the president, and that also helps.”

President Obama’s focus remains on the domestic economy.

“Our economy is getting stronger," he said. "The recovery is accelerating. All of which means that the last thing we can afford to do is to go back to the same policies that got us into the mess in the first place.”

The latest polls show the president would defeat any of the Republican contenders if the election were held today largely because the economy seems to be on the rebound, says Peter Brown.

“There is a general sense the economy is getting better and so the better perceived economic climate obviously rebounds to the president’s benefit,” he said.

But a Supreme Court decision on a challenge to the president’s health care law could also impact the election, says analyst Henry Olsen.

“Depending on what the Supreme Court rules, one side or the other could be particularly emboldened,” he said.

The high court decision is expected in June.