A few weeks ago, New York Times columnist Charles Blow was asked by a morning-show host on MSNBC why Rick Santorum keeps raising issues that don't need to be raised.

Instead of maximizing his image of being the grandson of a coal miner, father of seven and a man of faith, Santorum talks about the nausea he felt after reading John F. Kennedy's speech on church-state doctrine and the tendency of American colleges to brainwash youth into accepting the evils of liberalism.

Blow's answer, I think, was pretty much right:

This is part of who Rick Santorum is,.It is always going to surface. It has nothing to do with what's happening in the news. ... He has always wanted to fight on this ground and that is what he is doing and that is going to hurt him.

This is the Santorum who surfaced right before Sunday's GOP primary in Puerto Rico -- and it hurt. The island's primaries are rarely contentious, but this year's nomination had ramped up competition for its 20 delegates. That's why Santorum and rival Mitt Romney spent two days stumping in the commonwealth.

But during a town hall meeting, Santorum blow it all away when he said English had to be the first language of any American state. Later on, he clarified his remarks: "Like any other state, there has to be compliance with this and any other federal law. And that is that English has to be the principal language."

There is no such law nor is there any such language requirement enshrined in the US constitution. Nevertheless, a howler like that might have been ignored if Puerto Ricans weren't set to vote in November on whether to vote for statehood. As Albor Ruiz of the New York Daily News wrote:

His comments exploded like a bomb ... It is difficult to believe that even Santorum could have made a mistake so stupid it could guarantee a Romney victory.

It did. Romney won by a landslide, with 83 per cent of votes. Santorum got 8 per cent; Newt Gingrich got 3 per cent.

This is the longest GOP nomination in memory, and the longer it goes, the more moderate Romney appears compared to Santorum. Indeed, this all might be according to plan. Romney has already locked up a lead that's probably insurmountable. Now, he's pivoting from the rhetoric of radicalism to the rhetoric of moderation, where he's most comfortable. The more Santorum raises issues that don't need to be raised, the more Romney will look like the most reasonable guy in the room.

It strikes me that Puerto Rico has something to say about the future of the Republican Party -- ostensible moderates like Romney are more appealing to Latinos than fanatics. As Blow said, Santorum "scares the bejesus out of people."

Though Santorum is Catholic, and though Puerto Rico voters are largely Catholic, they, like their counterparts on the mainland, have rallied around the Latter-Day Saint. The future of the GOP is multicultural, but how can it do that without abandoning a xenophobic past? It probably can't. That is, unless Romney wins. That wouldn't be good for the U.S., but it might be for the GOP.