CHICAGO (CBS) — Mitt Romney had a clean sweep Tuesday, handily winning the Republican primaries in Wisconsin, Maryland and Washington, D.C.

But political analyst Stephen Caliendo says while Romney’s nomination may appear to be in the bag, his opponents are not likely to drop out as a result of Romney’s latest victories.

“I don’t think anybody is going to be dropping out right away. The thing about Rick Santorum is he’s got his home state on April 24 – he may not win that, he really may not – plus the northeastern states cluster, and but a bunch of southern states in May, and I think Rick Santorum is looking further down,” he said.

Still, exit polling has shown that even those who identify as “very conservative” have switched from Santorum to Romney, and at this point, many in the Republican Party are eager to put the primary behind them, Caliendo said.

“I think that there is some sense of, ‘Let’s get this thing over with, let’s get focused on the president,’ for sure. Mitt Romney picked up some very high-level endorsements from people who conservatives consider to be very credible on those issues, and I think that helped in Wisconsin for sure,” Caliendo said.

Meanwhile, Rick Santorum and Newt Gingrich remain in the race, and continue to campaign. Their continued presence could hurt Romney down the road, even after he is nominated, Caliendo said.

“It doesn’t affect it in a terribly divisive way if they’re picking up small numbers of people – that is, I would say that Ron Paul’s candidacy isn’t sort of dividing the party in any particular way. But to the extent that Mitt Romney is prohibited from getting majorities as opposed to just larger pluralities in some of these states, that could hurt him further down the road,” Caliendo said. “At the end of the day, he’s probably still going to be the nominee. But the fact that Gingrich and Santorum are refusing to drop out – they’re still campaigning, and they’re campaigning against Mitt Romney, not as much against President Obama.”