Just two days before the South Carolina primaries Gov. Rick Perry of Texas is set to end his bid for the Republican presidential nomination.

An aide confirmed Perry will not participate in the Republican debate Thursday evening, and will make a formal announcement to supporters and contributors in South Carolina at a press conference set for 11 AM.

It remains unclear whether Perry would endorse one of his Republican rivals before the South Carolina primary on Saturday. Perry was only polling in the single digits, but his withdrawal from the race could impact the outcome of the primary in South Carolina due to his conservative credentials.

Perry had a strong appeal with South Carolina’s evangelical voters.

Perry's decision to drop out of the race narrows the GOP field to four candidates.

Former House Speaker Newt Gingrich, seeking to position himself as the conservative alternative to Mitt Romney, has urged both Perry and Sen. Rick Santorum to drop out of the race to coalesce support among conservatives.

Ron Paul, while popular with some conservative voters, is not considered a serious contender for the nomination at this point.

However, analysts say it is doubtful Santorum will oblige Gingrich and drop out of the race, especially in light of the recent revelation that Romney's much reported 8-vote victory in Iowa was in fact a loss. In the final count Santorum defeated Romney by 34 votes.

Nonetheless, the media momentum of Romney's now-empty Iowa victory launched him to a certain victory in New Hampshire.

While pundits have ballyhooed the fact that no republican contender who has won both Iowa and New Hampshire has ever failed to secure the GOP nomination, Santorum and Gingrich are hoping the more conservative southern playing field and his Iowa reversal will hand Romney an upset.