Former House Speaker Newt Gingrich will formally pull out of the Republican presidential race next week, a campaign official said Wednesday.

His withdrawal further clears the way for former Massachusetts Gov. Mitt Romney, who has now claimed the unofficial mantle of the Republican nominee against President Barack Obama.

The only other Republican left in the race is Rep. Ron Paul of Texas, a libertarian who is far behind Romney in polls and has not won a single nominating contest.

Meanwhile, Texas Gov. Rick Perry Wednesday affirmed his support for Romney, after initially backing Gingrich's campaign following his own withdrawal from the race.

Mitt Romney has earned the Republican Presidential nomination through hard work, a strong organization, and disciplined message of restoring America after nearly four years of failed job-killing policies from President Obama and his administration, the Texas governor said in a statement reported by CNN.

So today I join the many conservative Republicans across the nation in endorsing Mitt Romney for President and pledge to him, my constituents, and the Republican Party than I will continue to work hard to help defeat President Obama.

Perry praised Romney's vision and record of private sector success. His announcement came following the reports that Gingrich would exit the race next week.

Gingrich agreed to endorse the former Massachusetts governor next week, although he has no aspirations to serve in a future Romney administration, spokesman R.C. Hammond told Reuters.

Newt's next role in life is as a citizen, Hammond said.

Gingrich plans to assist efforts to maintain Republican control of the House and help Republicans seize a majority in the Senate, Hammond said.

Gingrich had been defiant throughout the contest, declaring his intention to continue his campaign until the Republican National Convention even as he has dropped far behind in the delegate count and seen his campaign become saddled with millions in debt. But the former speaker suggested in a speech to supporters Tuesday, as Romney won five primaries, that he was prepared to concede to reality.

I want you to know over the next few days, we're going to look realistically at where we are at in the campaign, Gingrich told a meager crowd at a Tuesday night rally.

Gingrich also called on Republicans to rally behind Romney's candidacy, moving away from the combative rhetoric that has underpinned an often bitter campaign in which he has repeatedly attacked Romney for his record.

I want you all to understand that Gov. Romney is going to have a very good night and it is a night that he has worked hard for, for six years, Gingrich said. And that if he does end up as the nominee, I think every conservative in the country has to be committed to defeating Barack Obama and let's be very clear about this.

The former Speaker of the House went further on Wednesday, saying in a speech to the Gaston County GOP in North Carolina that it's pretty clear Governor Romney is going to be the nominee.

I think you have to at some point be honest with what's happening in the real world, as opposed to what you'd like to have happened, Gingrich said. Governor Romney had a very good day yesterday. He got 67 [percent] in one state, and he got 63 in other, 62 in another.

Gingrich surged into contention in December and sent tremors through the race when he decisively won the South Carolina primary, suggesting that he could capture the rural, working class and Tea Party-affiliated voters who had eluded Romney. But his campaign faltered from there, and his only victory since was in his home state of Georgia.

The possibility of Gingrich leaving the race could be a boon for Romney's campaign coffers, as Sheldon Adelson -- the billionaire casino magnate who has helped sustain Gingrich's campaign by pouring millions into the pro-Gingrich Winning Our Future Super PAC -- has hinted that he would throw his support to Romney should Gingrich drop out.