The Web site ricksantorum.com attracts more women than men, 60 percent of its visitors, a larger share than for the Web sites of other candidates, according to Nielsen ratings that were released last week. Among other things, there may be an empathy factor at work: A New York Times/CBS News poll taken this month found that 73 percent of Republican female voters said Mr. Santorum understood the needs and problems of people like them, compared with 52 percent who said the same about Mr. Romney.

“If it’s not his turn this time, it may be next time,” said Linda Terrebonne, 60, a retired court clerk who cheered for Mr. Santorum at a small rally last week in Harvey, La. “If he doesn’t win, I’ll go with the new guy, although I wouldn’t be really pleased about it.”

When Mr. Santorum took the stage in Mandeville on Wednesday, where his supporters had arrived rain-drenched, braving flash floods and a tornado watch, he did not sound as if he would be conceding the nomination any time soon. “I want to remind you what your duty is,” he told the crowd. “Reset this race.”

Louisiana may have a chance to help do that. Mr. Santorum, a former senator from Pennsylvania, is expected to do well in the primary on Saturday. Louisiana’s demographics and conservative political culture align with those of Southern states where he has prevailed. But beyond places like Mandeville, a Republican enclave north of New Orleans, Mr. Santorum will face a steep uphill climb toward the nominating convention in August.

But after Mr. Santorum’s speech, Lindsey Kersker, 45, a homemaker who lives in Mandeville, signed a check for $50.

“I can tell you why he does well with me, because he’s strong on family values and he’s very religious,” Ms. Kersker said. “I think that this country needs to have a renewal of its moral compass, and this is the man to do it.”

When the Harris sisters’ song, “Game On,” got wide attention on the Internet this month, it made them minor celebrities in conservative circles. People sing along to the words, “We’ve finally got a man who will stand for what is right.”