It probably isn’t accurate to say Rick Santorum is now the GOP frontrunner — delegate count is still most important — but it’s also not quite accurate to consider him nothing more than the latest not-Romney. Not only does the latest Gallup tracking poll show that his lead has expanded nationwide, but the Democratic National Committee by its recent attacks on him has also signaled that Santorum has arrived in this race:

“Santorum is leading in the polls nationally – it would be crazy to ignore him at this point,” a Democratic source with knowledge of the shift in strategy tells CNN.

“Rather than focusing on jobs, the economy, or any of the issues that matter most to Americans, he discussed man’s ‘dominion over’ the earth, repeated his patently false claim that prenatal health care is a plot to force more abortions, and questioned the need for public education,” said the DNC press release.

The second, just released Monday afternoon, hits Santorum on the economy.

“Rick Santorum has embraced the same philosophy that created the economic crisis. His tax plan would primarily benefit the very wealthy while adding $900 billion to the national deficit. And it would be a disaster for middle class families. Santorum has attacked the very idea of public education and criticized the Paul Ryan plan that would end Medicare as we know it because it did not go far enough. He opposed extending the payroll tax cut that saves the typical middle class family $1,000. And he opposed rescuing the auto industry which saved 1.4 million American jobs.” argues the DNC.

For its part, the Santorum campaign is unperturbed. A spokesperson told CNN that Obama has to be worried about Santorum because he has credibility to attack the president on health care, the bailouts, cap and tax, and the administration’s assault on religious liberty. That’s all true.

What about the DNC’s accusation against Santorum’s economic policies, though? All the issues the Dems cited are the issues of least concern to conservatives. I’m thrilled, for example, that Santorum didn’t support the payroll tax cut extension; he shouldn’t have. Obama won’t be able to attack Santorum for his repeated requests for a debt ceiling increase, either, and, while the president likes to pretend Santorum’s plan shows no concern for blue-collar workers or the manufacturing sector, it actually shows more concern — and more faith in the government — than most conservatives would like. Obama’s best line of attack against Santorum would have been on social issues — but he’s even turned the tables on himself on that one.