Waste of an endorsement, but okay. I doubt Santorum gets much of a bump out of this; maybe 5 points but not enough to make him flavor of the month.
It wasn't really an endorsement in case you didn't watch the video and read the small print.
She sounds chicken to endorse him for fear he'd flop and drop out after Iowa proving her political stock is worthless. Her strategy seems trying to boost Santorum while also letting herself save face. If he surges, she could get credit and then jump on the bandwagon safely. If he flops, she never endorsed him.
Glenn Beck also called Santorum the next George Washington (probably a dogwhistle that we'd form a new theocratic country) but stopped short of endorsing him.
A Santorum or Bachmann surge looks more unlikely the closer we get but even one in the final week into Iowa wouldn't be that crazy by the standards of this cycle or even Iowa's track record.