WASHINGTON -- Former Republican presidential candidate Rick Santorum is releasing the delegates he won during the GOP primary race to Mitt Romney.

The former Pennsylvania senator informed supporters of his plans during a Thursday night conference call. He's expected to release a public statement Friday followed by a formal letter.

That's according to a senior aide who isn't authorized to speak publicly.

The decision is a formality that frees more than 200 delegates to support Romney at the party's national convention next week in Tampa, Fla.

Santorum became Romney's top opponent for the GOP nomination. His withdrawal from the race in April cleared the way for Romney's general election fight against President Barack Obama.

Santorum won a total of 245 delegates during the primary, according to a count by The Associated Press.

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  • "Love And Marriage" (Frank Sinatra)

    <a href="http://www.huffingtonpost.com/2011/11/21/rick-santorum-gay-marriag_n_1105063.html" target="_hplink"><strong>(Nov. 21, 2011) --</strong></a> While speaking at Iowa's Thanksgiving Family Forum, Santorum let loose on his views about gay marriage. "There's a basic and central value," he said. "The family is the bedrock of our society. Unless we protect it with the institution of marriage, our country will fall." (AP Photo/Charlie Neibergall)

  • "Sexual Healing" (Marvin Gaye)

    <a href="http://www.huffingtonpost.com/2011/12/06/rick_santorum_gay_marriage-sex-_n_1131485.html" target="_hplink"><strong>(Dec. 6, 2011) -</strong></a> Santorum openly voiced his disapproval of gay marriage, explaining how gay sex is not "equal" to hetero sex. (Photo by Scott Olson/Getty Images)

  • "Glitter In The Air" (Pink)

    <strong><a href="http://www.huffingtonpost.com/2012/01/21/rick-santorum-glitter-bombed-photo_n_1221447.html" target="_hplink">(Jan. 21, 2012) --</a></strong> Moments after finishing in third place at South Carolina's GOP primary, Santorum was glitter-bombed by Occupy Charleston protesters. (AP Photo/Rainier Ehrhardt)

  • "I Melt With You" (Modern English)

    <a href="http://www.huffingtonpost.com/2012/02/07/rick-santorum-global-warming-hoax_n_1260168.html" target="_hplink"><strong>(Feb. 7, 2012) --</strong></a> Santorum revealed his thoughts on climate change, targeting rivals Mitt Romney and Newt Gingrich as buyers into the "bogus" science. The former Pennsylvania senator vowed that he has never believed in "the hoax of global warming." (Photo by Ben Garvin/Getty Images)

  • "Poker Face" (Lady Gaga)

    <a href="http://www.huffingtonpost.com/2012/03/01/rick-santorum-frat_n_1312924.html" target="_hplink"><strong>(March 1, 2012)</strong> --</a> Santorum's fraternity brothers reminisced about his time at Penn State, revealing that the GOP presidential contender was a regular poker player in college. (Photo courtesy of Penn State University)

  • "Born In Puerto Rico" (Paul Simon)

    <a href="http://www.huffingtonpost.com/2012/03/14/rick-santorum-puerto-rico-english-statehood_n_1345464.html" target="_hplink"><strong>(March 14, 2012) --</strong></a> On a campaign trip to San Juan, Santorum tied Puerto Rico's chances for statehood to the country employing English as its official language. "Like any other state, there has to be compliance with this and any other federal law," Santorum said. "And that is that English has to be the principal language." Of note: the U.S. Constitution does not contain an official written language requirement for statehood. (Photo by Christopher Gregory/Getty Images)

  • "Ridin' Dirty" (Chamillionaire)

    <a href="http://www.huffingtonpost.com/2012/03/16/rick-santorum-war-on-porn_n_1353383.html" target="_hplink"><strong>(March 21, 2012) --</strong></a> Santorum highlighted pornography as one of his primary campaign concerns, vowing to place a greater focus on federal obscenity laws. "America is suffering a pandemic of harm from pornography," he wrote on his website. "It contributes to misogyny and violence against women. It is a contributing factor to prostitution and sex trafficking." (Photo by Scott Olson/Getty Images)

  • "Life Ain't Easy" (Mac Miller)

    <a href="http://www.huffingtonpost.com/2012/03/29/rick-santorum-campaign-gop-primary_n_1389601.html" target="_hplink"><strong>(March 29, 2012) --</strong></a> Entering month four on the campaign trail, Santorum expressed discontent about the financial mountain between him and rival Mitt Romney. "I'm not complaining. I'm not going to be whining about this," Santorum insists. (Photo by Scott Olson/Getty Images)

  • "Undone -- The Sweater Song" (Weezer)

    <a href="http://www.huffingtonpost.com/2012/04/10/rick-santorum-exits-race-_n_1415454.html" target="_hplink"><strong>(April 10, 2012) --</strong></a> Santorum dropped out of the presidential race, and along with him went the signature sweater vest.

  • "I Miss You" (Blink 182)

    <a href="http://www.huffingtonpost.com/2012/08/06/rick-santorum-rnc-speech-convention_n_1749911.html" target="_hplink"><strong>(Aug. 6, 2012) --</strong></a> After months of campaigning against Romney, Santorum was named a speaker at the 2012 Republican National Convention. Reuters reported there were worries among some Romney advisers that a Santorum speech would deviate from Mitt's message. (Photo by Chip Somodevilla/Getty Images)