His polling numbers stalled out for almost a year, his campaign mired with miscues and poor performances, and operating under a threat of having campaign dollars cut off by the Republican National Committee and the National Republican Senatorial Committee, Sen. Rick Santorum did what any desperate candidate would do: he got a third party candidate into the race.

According to Santorum campaign insiders, Santorum knew about plans by his supporters to get Green Party candidate Carl Romanelli into the Pennsylvania Senate race, in hopes that Romanelli would siphon off votes from Democrat nominee Bob Casey, Jr.

Santorum continues to trail Casey by double digits in all polling done so far, but in those conducted in the past two weeks, Santorum had cut Casey’s lead from the mid-20s to the low teens. Santorum campaign staff say they have seen internal polling that shows Santorum down only 10 percentage points, though Santorum’s internal polls have been called highly optimistic.*

Local Pennsylvania newspapers have begun questioning just how Romanelli was able to get on the ballot, particularly under the demanding requirements set by the state of Pennsylvania: petitions with the signatures of registered voters equal to 2 percent of the highest vote-getter from the most recent state election. That race was for state treasurer and the winner of that race was Casey, with 3.4 million votes.

Romanelli got the 67,070 signatures he needed, but with the help of Republicans who have been working mostly for Santorum. According to sources inside Santorum’s campaign, Romanelli is financially backed by at least one member of Santorum’s finance committee who, while supportive of the Green Party, has also been a supporter of Santorum due to his position on life issues.

“We started hearing about the possibility of a Romanelli run a couple of months ago around the office, but it was being treated like a big secret,” says a Santorum insider. “A bunch of Rick’s supporters were being asked to support Romanelli’s petition drive. In fact, the Associated Press reported that Santorum financial backers provided as much as $30,000 to Romanelli. Santorum financial backers also assisted in finding petition circulators.”

Romanelli’s arrival as a candidate comes at a critical time for Santorum. Across the country, Republican Senate candidates are showing competitive life in Washington state, Minnesota, New Jersey, and Maryland. Meanwhile the national party is committed to helping sitting Republican candidates in Missouri and Montana who are facing tough races in the fall.

Santorum had informed party officials that he believed he’d require as much as $1 million a week, perhaps more, to win his race against Casey. “And he wasn’t talking about footing that bill himself,” says an RNC staffer. “He expected the national party and the Senate campaign committee to help. That’s money that would have gone to more competitive races.”

Now Santorum has his polling numbers looking up a bit, a third party to peel away some votes from Casey, and three months to right what had been a badly listing ship. Something Santorum apparently believes is doable.

And you won’t hear Romanelli whistling, “It’s Not Easy Being Green.” When you’re bought and owned by another party’s candidate, it’s the easiest job in the world.

*UPDATE: For more on Santorum’s improving numbers, see this Prowler entry at AmSpecBlog.