The Ohio primary results have all eyes on the Buckeye State on Super Tuesday.
HuffPost's Mark Blumenthal reports:
Ohio will allocate its 48 congressional district delegates on a winner-take-all basis within each district, and uses a proportional allocation for its 15 at-large delegates. The close nature of the race statewide means the candidates are likely to split the state's delegates. Santorum's task is made even harder by his failure to qualify for any delegates in three of Ohio's 16 congressional districts, and by his failure to fill delegate slates in six more, leaving him potentially ineligible for 18 of Ohio's 63 pledged delegates on Tuesday.
On Super Tuesday, the following nine states are also holding primary and caucus contests: Alaska, Georgia, Idaho, Massachusetts, North Dakota, Oklahoma, Tennessee, Vermont and Virginia.
From delegates to endorsements, click here for a rundown on who's ahead in the Republican race.
Check out the live blog below for the latest Super Tuesday developments.