PRINCETON, NJ -- Rick Santorum goes into Wednesday night's Republican presidential debate in Arizona enjoying an eight-percentage-point lead over Mitt Romney in national Republican registered voter preferences for the GOP nomination, 35% to 27%. Santorum held an identical lead in the latest full week of Gallup Daily tracking, from Feb. 13-19, and according to those data, his biggest advantages over Romney -- of 18 points or better -- are among Midwesterners, weekly churchgoers, and political conservatives.
The result is a heavily lopsided picture, with conservatives, weekly churchgoers, and Midwesterners propelling Santorum into the lead, while nonconservative and less religious segments of the party -- as well as those in the other three regions of the country -- show, at best, slim support for Santorum.
These results are based on 1,641 Republicans and Republican-leaning independents who are registered to vote.
Santorum also leads Romney by more than 10 points among Republican adults 35 and older, those without a college degree, and those in households earning less than $90,000 per year, patterns that are generally consistent with his strong lead among conservatives and heavy churchgoers.
However, Santorum is notably weak among young Republicans -- those aged 18 to 34 -- who still favor Romney by 13 points, 33% vs. 20%. In fact, more young Republicans currently favor Ron Paul (26%) for the nomination than Santorum -- a finding consistent with Paul's relatively strong performance among young Republicans throughout the campaign.
Men, college graduates, and high-income Republicans (those earning $90,000 or more annually) essentially divide their support evenly between Santorum and Romney.
Santorum Has Surged Among Women, Conservatives, and Older Adults
Santorum quickly rose to the top of the Republican pack after his impressive wins in the Minnesota, Colorado, and Missouri Republican contests on Feb. 7. Within the first week after those victories, Romney's advantage over the former Pennsylvania senator in weekly averages of Gallup Daily tracking was cut from 19 points to 8 points. Now, a week later, Santorum has the 8-point advantage.
Santorum's surge is evident among most subgroups of Republicans, but is particularly strong among women. His positioning versus Romney has improved by 22 points among this group, from a deficit of -12 during the week of Feb. 6-12 to a lead of +10 from Feb. 13-19.
Similarly, Republican support for Santorum rose sharply among those 55 and older (+21), conservatives (+18), weekly churchgoers (+18), college nongraduates (19%), those in households earning less than $90,000 (18%), and those living outside the East.
Santorum after his Feb. 7 wins is benefiting from a wave of increased support that has come from just about every major subgroup in the Republican Party. Despite this, the profile of Santorum's GOP supporters remains decidedly conservative and highly religious, as well as concentrated in the Midwest.
Santorum's strong showing in that region could partly stem from his victories in the Minnesota and Missouri Republican contests on Feb. 7 and could position him well in the crucial upcoming Michigan and Ohio primaries. Santorum's disproportionate strength among conservatives and highly religious Republicans could also make it difficult for Romney to win back many of those voters.
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Results are based on telephone interviews conducted as part of Gallup Daily tracking Feb. 13-19, 2012, with a random sample of 1,641 adults, aged 18 and older, living in all 50 U.S. states and the District of Columbia.
For results based on the total sample of Republicans and Republican-leaning independents who are registered to vote, one can say with 95% confidence that the maximum margin of sampling error is ±3 percentage points.
Interviews are conducted with respondents on landline telephones and cellular phones, with interviews conducted in Spanish for respondents who are primarily Spanish-speaking. Each sample includes a minimum quota of 400 cell phone respondents and 600 landline respondents per 1,000 national adults, with additional minimum quotas among landline respondents by region. Landline telephone numbers are chosen at random among listed telephone numbers. Cell phone numbers are selected using random-digit-dial methods. Landline respondents are chosen at random within each household on the basis of which member had the most recent birthday.
Samples are weighted by gender, age, race, Hispanic ethnicity, education, region, adults in the household, and phone status (cell phone only/landline only/both, cell phone mostly, and having an unlisted landline number). Demographic weighting targets are based on the March 2011 Current Population Survey figures for the aged 18 and older non-institutionalized population living in U.S. telephone households. All reported margins of sampling error include the computed design effects for weighting and sample design.
The questions reported here were asked of a random half-sample of respondents for seven nights on the Gallup Daily tracking survey.
In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls.
For more details on Gallup's polling methodology, visit www.gallup.com.