Rick Santorum, the former U.S. senator from Pennsylvania, basically tied Mitt Romney in nationwide polling about the GOP primaries. The jump comes after Santorum won votes in Colorado, Minnesota and Missouri last week.

The sweep pushed Santorum to 30 percent support in a poll this week by the Pew Research Center. The same poll showed 28 percent support for Romney. But it's not all good news for Santorum: The same poll showed that 31 percent of those asked did not know enough about Santorum to rate him.

Santorum's campaign worker said they plans to use the $4 million in donations made this week to help spread the word.