(CNN)Former Pennsylvania Sen. Rick Santorum is ending his presidential bid, two Republican sources told CNN.
He is expected to make the announcement Wednesday night and will endorse a candidate.Santorum won the 2012 Iowa caucuses and ended that race with the second-most number of delegates to eventually GOP nominee Mitt Romney.
But he was unable to capture any momentum this year, despite extensive barnstorming efforts in Iowa.He is the third Republican presidential candidate to drop out after Monday's caucuses. Mike Huckabee ended his campaign that night, and Rand Paul suspended his campaign Wednesday morning. Santorium joins Perry, Walker and Jindal.
