Scott Olson/Getty Images

DES MOINES, Iowa-Iowa's Secretary of State Matt Schultz will be endorsing Rick Santorum Friday, ABC News has learned.

The campaign teased the endorsement as a "major announcement" and it is a big boost for the candidate who has spent the most time campaigning in the state.

During the last cycle, Schultz backed Mitt Romney, who shares his Mormon faith.

Their shared religion as well as the previous endorsement in 2007 will definitely be interpreted as a swipe to the former Massachusetts governor.

"Matt Schultz is a rising star within the Iowa Republican party," Tim Albrecht, caucus veteran and communications director for Iowa governor Terry Branstad said. "His endorsement is another in a long line of impressive gets for the Santorum campaign. Rick Santorum's organization here is real and that will be reflected on caucus night."

Santorum was endorsed by both evangelical leader Pastor Cary Gordon and conservative activist Chuck Laudner recently.

He is also the only campaign waging a traditional Iowa caucus campaign.

The former Pennsylvania senator has campaigned in all 99 counties and he is both shoring up precinct captains and county chairs and publicizing them, usually a standard for any campaign that wants to win the caucuses.

However, there hasn't been much movement in the polls for Santorum. According to this week's ABC News/Washington Post poll he only received 7 percent support with likely caucus goers.

Schultz's brother also works for the Santorum campaign. The event will be held tomorrow evening in Johnston, Iowa.

He also announced this week that he would participate in the Newsmax/Ion debate hosted by Donald Trump.

The only other candidate who will participate is Newt Gingrich, all the others have declined.

On Thursday evening Santorum issued a scathing rebuke to his rivals.

"Many of my opponents jockeyed to be the first to fly up to New York and use Donald Trump for a photo op and no doubt try and secure an endorsement," Santorum said in a statement. "But when Donald wants to moderate a debate - they refuse to attend. That's what's so wrong with politics today - hypocrisy. At this critical time in our nation's history, just weeks before Iowan's cast this important vote - many of the other candidates want to hide behind TV ads and mail pieces. We plan to be there front and center in person to debate Newt directly, and if it's just the two of us, we're fine with it."

And it looks like he's going for The Donald's endorsement. The statement ends like this:

"Donald Trump knows business and knows global markets - and we all know he'll be able to bring in a broad audience. And let's be honest, at least Donald Trump will have more in common with the candidates than with the vast majority of past moderators," the release read.