The first Republican presidential hopeful to visit all 99 counties in Iowa, former U.S. Sen. Rick Santorum of Pennsylvania is showing signs of life in the Hawkeye State as he continues his campaign for the GOP nomination.

With two weeks to go, Santorum has broken double digits for the first time in a poll of Iowa. He trails U.S. Rep. Ron Paul of Texas, who now leads the pack of Republican presidential hopefuls in Iowa, while former U.S. House Speaker Newt Gingrich has come crashing down in the Hawkeye State, according to a poll released late Sunday from Public Policy Polling, a firm with connections to prominent Democrats on the national level.

The PPP poll of likely Iowa caucus voters has Paul, who finished a strong second in the Iowa Republican straw poll in August, ahead with 23 percent, followed by former Gov. Mitt Romney of Massachusetts with 20 percent. Gingrich, who had been leading earlier in the month, takes third with 14 percent, while three conservatives -- U.S. Rep. Michele Bachmann of Minnesota, Gov. Rick Perry of Texas and Santorum -- are tied for fourth, with 10 percent apiece. Two former governors who have focused on New Hampshire instead of Iowa -- Jon Huntsman of Utah and Gary Johnson of New Mexico -- trail in the low single digits. Huntsman takes 4 percent while Johnson garners 2 percent. The poll of 597 likely Iowa Republican caucus voters was taken from Dec. 16-18 and had a margin of error of +/- 4 percent.

Santorum keeps plugging away and, on Monday, unveiled the endorsement of Siouxland radio talk-show host Sam Clovis, a favorite of Iowa conservatives.

"Sam Clovis is a true voice for conservatism in Siouxland,” Santorum said on Monday. “He has stood tall for conservative principles and constitutional government both on the air and in the classroom. Sam is a respected voice whose endorsement will be important to his many listeners, so to have his support today is a terrific boon to our campaign and honor to receive. The momentum continues building for us, and I am thrilled to have Sam as part of our team as we put our plan to win the Iowa caucuses into action!"

"Many listeners and interested Iowans are always asking me who I will be supporting in the upcoming caucuses. I think it's time I take a stand and let people know,” Clovis said. "My ideal candidate must be a conservative who believes in a constitutionally limited government, fiscal responsibility, strong national defense and unflagging devotion to life and traditional marriage."  

Santorum will continue to focus on Iowa this week. He appeared on Clovis’ show on Monday morning before heading to campaign events in Osceola, Des Moines and Indianola. The campaign trail takes him throughout the Hawkeye State on Tuesday and Wednesday.

Still, there has been bad news for Santorum in Iowa. Last week he lost one of his chief volunteers in the Hawkeye State -- Wendy Jensen of Ames. Jensen was a leading Republican activist in Iowa and a staunch Santorum backer.

"The news of Wendy's passing is absolutely heartbreaking,” Santorum said on Monday. “I just had the opportunity to visit with Wendy on Wednesday evening, where she always was -- hard at work volunteering for our campaign. She was absolutely amazing. Wendy may have been small in stature, but she had the heart of a lion. My deep condolences go out to her entire family and loved ones on her passing. She will be dearly missed."

"Among the rewarding aspects of political campaigns is the opportunity to meet good people and build lasting relationships,” said Cody Brown, Santorum’s Iowa director, on Monday. We had the benefit and privilege to have met Wendy Jensen who became an integral part of our tight-knit Santorum 'family.' We knew her not only as our top phone banker, but as our campaign's delight and an inspiration for us all."

On Monday, Santorum also garnered the endorsement of novelist Brad Thor, a frequent guest on Glenn Beck’s radio show.