|Santorum's statements were treated negatively in the mainland press. However, this doesn't necessarily indicate that Puerto Ricans themselves were extremely upset about Santorum's views - or that they even knew about Santorum's comments in the first place. I've searched out four Puerto Rican newspaper articles (here, here, here, and here) about Santorum's comments. Three are pretty short and perfunctory; one is longer and more negative. Does this mean that the average Puerto Rican was aware of and upset by Santorum's comments?
And just how important was the primary to the average Puerto Rican? Of course, America's primaries have less to do with Puerto Ricans than people on the mainland. But just how much less so? To find the answer, we have to look for hints. The Puerto Rican primary results did make the reel of top news stories in Puerto Rican newspapers.
There is also turn-out. In the 2008 Democratic primary, turn-out was above that of Connecticut but below that of Oregon and Oklahoma. This matches the relative population of these respective states. In the 2012 Republican primary, however, the number of Puerto Ricans who voted was less than half the number of Oklahomans. So it seems that the 2012 Republican Primary was far less important to Puerto Rico than the 2012 Democratic Primary.
It's a difficult question how Puerto Rico would have voted without Santorum's statements. Puerto Rico is very different from the American mainland; therefore it's not easy to predict its political behavior.
In general, Puerto Rico seems to go for the more well-known, establishment candidate. And upstart Santorum is a bad cultural fit for Puerto Rico. It's pretty hard to see Santorum winning Puerto Rico even without his English comments.
Nevertheless, Santorum ended up getting 8% in Puerto Rico. That's a very, very low number. In 2008, despite his weakness amongst Hispanics, Barack Obama still ended up getting 31.2% of the Puerto Rican vote. It's not unreasonable to think that Santorum would have done similar if he'd not argued that Puerto Rico make English its official language to gain statehood. At least he probably would have broken into double-digits.
All in all, as stated before, place any group under the right adversarial circumstances, and it will vote very strongly for one side and against another. Rick Santorum, with his English comments, put Puerto Ricans in a very adversarial circumstance. A few days later Puerto Rico gave his opponent ten times the number of votes Santorum won.