Former Pennsylvania Senator Rick Santorum on Sunday accused President Obama of being a "sore winner" in his dealings with Republicans.

"That's the problem with this administration. They don't - they're not very gracious winners. And I always said, you know, there's one thing worse than a sore loser, and that's a sore winner. And the president's a sore winner," Santorum told me during our Powerhouse Roundtable on "This Week." "He could get something done on deficits and entitlements, but he's got to move his people to do that, instead of forcing Republicans always to come his way. And that's the problem."

He also said there is real opportunity to achieve bi-partisan immigration reform.

"I think the Republicans are ready to do something on immigration. And, I mean, you saw Marco Rubio's plan, which is pretty-pretty far down the road, looks a lot like what President Bush put forward four years ago," Santorum said. "Yes, they're willing to do it. But they're not willing to give the president everything he wants, because I think they believe the rule of law still matters in this country."

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Santorum advised Congressional Republicans to stand their ground against Obama's gun proposals.

"I think we should stick to our guns," Santorum said.

Santorum clashed with former Democratic Governor of Michigan Jennifer Granholm, who supports Obama's efforts and also was on our roundtable.

"Deer don't wear armor. Why do you need an armor- piercing bullet?" Granholm said.

"But criminals could…having the ability to defend yourself is something that is a right in our country," Santorum responded.

Santorum, chairman of Patriot Voices - a group that promotes conservative issues - also tweaked the president for what he argued was a lack of action to address the "glorification of violence" in film and TV.

"Not one thing the president did dealt with Hollywood and gun violence and video games and all the glorification of violence," Santorum said. "Why do you need to protect Hollywood?"