"The Latino vote makes a difference, and can make the difference in a number of critical states," he said at a breakfast sponsored by The Christian Science Monitor. He argued that both from a "purely political perspective" and from a good policy standpoint, the GOP needed to do better at crafting policies aimed at Hispanic voters, including changes to immigration.

He praised Hispanics as "Christians, family-oriented entrepreneurs" who work "really, really hard" and said they needed to be embraced by, not ostracized from, the GOP and society as a whole. "We're not going to deport 12 million people and in many cases we shouldn't," he said.

Barbour also said he was a "huge fan" of both Sen. Marco RubioMarco Antonio RubioSenate moving ahead with border bill, despite Trump Hillicon Valley: New FTC chief eyes shake up of tech regulation | Lawmakers target Google, Huawei partnership | Microsoft employees voice anger over ICE contract Lawmakers urge Google to drop partnership with Chinese phone maker Huawei MORE (R-Fla.) and New Mexico Gov. Susana Martinez (R) — two prominent Hispanic Republicans — and later mentioned Rubio as a strong option for presumptive GOP nominee Mitt Romney to choose as vice president, adding that he didn't think a "running mate has a major impact on what people think" about the top of the ticket.

He also argued that the most important thing in picking a vice president was first to "do no harm," and second to pick someone who could help in a particular state — like Rubio could in Florida, Sen. Rob PortmanRobert (Rob) Jones PortmanSenate moving ahead with border bill, despite Trump 13 GOP senators ask administration to pause separation of immigrant families Lawmakers, businesses await guidance on tax law MORE could in Ohio or Virginia Gov. Bob McDonnell could in his state — and said Virginia and Ohio were the most crucial states on the presidential map.

As for Romney, Barbour acknowledged the former Massachusetts governor was the "least conservative" choice for the GOP nominee, but added that his selection was proof Republicans were still a "broad party."

His comments were in contrast from remarks earlier this week from former Florida Gov. Jeb Bush (R), who said his father, former President George H.W. Bush, and former President Reagan would have struggled in the modern Republican Party.

"We are a broad party. There are a lot of people in the Republican Party who are not that conservative, including our nominee for president," Barbour said. "[Romney] was the least conservative of the serious candidates and he won the nomination, and the party totally united behind him."

Barbour predicted a "very hard, very tough, very negative and probably a very close race" between Romney and President Obama, arguing that the race would remain a referendum on the president's record rather than a choice between the candidates — and that if that's true, Obama "can't win this."

"The Obama people say 'this is not a referendum on Obama's record.' That's like me saying 'I haven't gained much weight lately,' " he joked.

Barbour warned, however, that Obama was planning to "carpet bomb" Romney on personal issues, and that if his attacks stuck, it could hurt the Republican Party's chances.

Barbour, who has been heavily involved in fundraising for the GOP outside groups American Crossroads and Crossroads GPS, called the current campaign finance laws a "bad system" and argued people should be able to make unlimited contributions to the candidates and parties so that groups like his were unnecessary.

He also said the GOP's chances of capturing the Senate were "not as easy" as they appeared 18 months ago because of good recruitment on the Democratic side and Sen. Olympia Snowe's (R-Maine) retirement, but predicted if the presidential race is close, the Senate's composition will be as well. He warned that the House was not a slam dunk for the GOP, but said Obama would have to win by 10 points for Republicans to lose control of the House.