WASHINGTON -- New polls show Rick Santorum leading by double digits over Mitt Romney in Saturday's Republican presidential primary in Louisiana. Romney's apparent deficit there is consistent with prior losses in other Southern states, but Louisiana's proportional allocation of convention delegates means that former Sen. Santorum (R-Pa.) is unlikely to gain much ground even if he wins Louisiana's popular vote by a wide margin.
The two newest telephone polls, both conducted using automated, recorded voice methodologies, show nearly identical results. Public Policy Polling (PPP), a firm that polls for local Democratic candidates, finds Santorum leading Romney by 14 percentage points, 42 to 28 percent, followed by former House Speaker Newt Gingrich (R-Ga.) at 18 percent and Rep. Ron Paul (R-Texas) at 8 percent, in a survey conducted March 21 to 22. Rasmussen Reports, in a poll fielded on March 21, finds Santorum leading by 12 points (43 to 31 percent), with Gingrich at 16 percent and Paul at 5 percent.
A third automated survey conducted on Monday before Tuesday's Illinois primary, by the Republican firm Magellan Strategies, gave Santorum a similarly sized margin over Romney (37 to 24 percent), but gave Gingrich a larger share of the vote (24 percent).
A recent decline in support for Gingrich is consistent with the apparent late trends in Illinois. Although the final polls there showed Gingrich winning between 12 and 14 percent support, he received only 8 percent of the actual vote.
Romney's deficit in Louisiana comes as little surprise, given his previous losses in other Southern states, such as South Carolina, Alabama, Mississippi and Tennessee. Some argue that Louisiana could be "fertile ground" for former Massachusetts Gov. Romney, given that the state is less rural than others in the South and includes fewer white evangelicals (50 percent in the 2008 exit poll) than other states where evangelicals voted in high numbers, like Alabama (75 percent) and Mississippi (80 percent) this year. The most recent Louisiana polls, however, indicate that Santorum is well positioned to win the popular vote there.
The problem for Santorum is that Louisiana's delegate allocation rules will prevent him from translating even a large popular vote victory into a significant delegate gain. Louisiana will send 46 delegates to the Republican convention in Tampa, Fla., but will choose only 20 on the basis of Saturday's vote. Louisiana's rules allocate those 20 delegates proportionally to any candidate that receives more than 25 percent of the vote (the remaining 26 delegates will be selected by a subsequent state convention and will remain technically unpledged).
If Santorum wins by a margin that matches the average of the PPP and Rasmussen polls (43 to 30 percent), then he will receive just 9 delegates to 6 for Romney. The remaining 5 delegates -- a number proportionate to the share of the vote received by other candidates who did not clear the 25 percent threshold -- would be sent to Tampa, as uncommitted delegates. In effect, the apparent decline in Gingrich's vote appears to be helping Romney in the delegate chase, by boosting Romney safely over the 25 percent threshold necessary to win delegates.
What if Gingrich's support collapses completely in Louisiana? The PPP poll also included a hypothetical vote without Gingrich, and that shows much of Gingrich's support shifts to Santorum, expanding his lead over Romney to 22 points (53 to 31 percent). But even with a margin that big, Santorum would net just two additional delegates, winning 11 to Romney's 6, with 3 delegates remaining uncommitted.
So Santorum may be headed toward a big popular vote win in Louisiana on Saturday, but even a huge margin of victory will do little to help Santorum gain ground in the all-important contest for Republican convention delegates.
Update: The American Research Group has released another survey that shows Santorum with a slightly larger lead over Romney (43 to 27 percent) than the two most recent automated polls. The new poll, conducted using live interviewers from March 20 to 22, also showed Gingrich with slightly more support (20 percent) than the other recent polls, and just 6 percent choosing Paul.
CORRECTION: The delegate calculations in the original article have been corrected to reflect the Louisiana GOP primary rules as reported by the Associated Press and NBC News. The summary of the rules at theGreenPapers.com, used as the basis of the original calculations, did not specify that votes for candidates that do not clear the 25 percent threshold will be used to allocate uncommitted delegates.