Gingrich expected to leave GOP presidential race Wednesday, sources say

April 25, 2012: Newt Gingrich talks with students at Thomas Jefferson Classical Academy in Rutherford, N.C. (AP)

Newt Gingrich plans to formally drop out of the Republican presidential race on Wednesday, senior sources told Fox News.

The campaign earlier had been expected to make the exit official on Tuesday, but has pushed the announcement back by a day.

The former House speaker may endorse presumptive GOP nominee Mitt Romney, something Rick Santorum has not yet done.

Gingrich is leaving the race after struggling to follow up his comeback victory in the January South Carolina primary. Gingrich went on to win his home state of Georgia, but watched as Santorum won far more states and emerged as the Republicans' most viable alternative to Romney.

Both candidates' campaigns confirmed their exit from the race this month.

Fox News' Bret Baier contributed to this report.