Different regions of South Carolina comprise varying electorates and how the candidates fair in each region could determine how they perform during the primary.
From Mount Pleasant to Mauldin and everywhere in between, various trends exist that make some counties more or less favorable for certain candidates.
For example, voters in the largely evangelical Upstate counties generally . Sen. Rick Santorum and Gov. Rick Perry have attempted to seize that opportunity, making most of their campaign stops in Greenville, Spartanburg and Greer.
The Lowcountry, where Gov. Mitt Romney has spent much of his time, is home to more moderate voters and a solid base of retired miltary and servicemembers.
And the Midlands provide a mix of Lexington, a Republican heartland, and Richland, which tends to lean farther left.
Former House Speaker Newt Gingrich's campaign headquarters is in the Upstate, but he has spent more time in the Midlands than his opponents, where may cause him the fewest problems.
Those three population centers make up about 50 percent of the entire South Carolina electorate.
During 2008, Sen. John McCain carried the state by winning the Lowcountry and the Midlands. Former Ark. Gov. Mike Huckabee, the choice among social conservatives, won most of the Upstate counties, but it wasn't enough to carry him past McCain.
Here's a county-by-county breakdown of the 2008 Primary (from CNN):County: McCain (%): Huckabee (%): Romney (%):
Voter Turnout: Greenville: 26 29 17
59,004 Lexington: 33 29 17
34,485 Charleston: 45 16 19
34,226 Spartanburg: 27 34 13
30,150 Richland: 38 22 19
28,667 Horry: 33 28 19
25,570 York: 24 36 11
20,766 Beaufort: 42 16 26
19,636 Aiken: 35 32 15
18,293 Berkeley: 38 26 15
14,878 Pickens: 28 39 10
14,651 Dorchester: 39 23 17
"It makes some sense to play to your strengths," said Charles Bierbauer, former White House correspondent and dean of the University of South Carolina journalism department.
"For Romney to go Upstate, if indeed the demographics hold up, he could be expending efforts and enegries and funds in a place where he’s not going to be the winner."
Bierbauer said data from previous election cycles could provide clues about which candidates would succeed in which counties, but also cautioned against drawing too many conclusions.
For example, McCain and Romney have both fared well in the Charleston-area, but perhaps for different reasons.
"McCain did well in the Lowcountry because it’s where you’ve got the military bases, military retirees," Bierbauer said. "That was one of his strengths. I'm not sure that we have a candidate with those matching credentials this time."
Bierbauer also said that growing areas of the state, like the Pee Dee, would play a significant role in the primary.
A primary tracker map organized by the Washington Post shows that when candidates have ventured away from the three main regions, they've generally travelled to the Pee Dee or the Beaufort area.
South Carolina Elections Commission spokesman Chris Whitmire said the lack of a Democratic primary this year could also have an impact.
"You may see a person who affiliates with the Democratic party who might not care, so they might not go to the polls at all," Whitmire said. "So a highly democratic county in the Midlands or Lowcountry may not see as much turnout [as 2008]. But a county in the Upstate where you see a highly Republican population, you might see a higher turnout."
Because South Carolina does not require registration by party, Whitmire said there was no reliable way to track how many Democrats participated in the open Republican primary.
Voters in Lexington County supported McCain during 2008, but Lexington Election Commission Director Dean Crepes said that didn't mean much for 2012.
"I'm not really sure who [Lexingtonians] are leaning toward because it changes every day," Crepes said.
Crepes said absentee voting had been steady during recent weeks and that he expected a better turnout this year because of the lack of a Democratic contest.
"We're definitely looking for a greater turnout than 2008," Crepes said. "Some polling places that had 400 voters in '08 might have 800 this year."
Crepes said no single issue was most important to Lexington voters and estimated a 50-50 split between those focused on social issues and those focused on the economy.
Ultimately, Bierbauer said, while county voting patterns may help a candidate plan his campaign, it won't decide the election.
"The essential question in terms of the voting on Saturday is whether the social conservatives or religious conservatives, that part of the electorate, coalesces around one candidate," Bierbauer said.
"If Santorum and Gingrich and, to a lesser degree, Perry divvy up that contingent, then Romney can get by with a 30 percent win."