Some critics are taking aim at Republican presidential candidate Ted Cruz’s “tithing” history, claiming that he contributed less than 1 percent of his income to charitable causes between 2006 and 2010 — much less than the 10 percent that is embraced as the standard by many Christians.

A new evangelical group called Americans United For Values is slamming Cruz in a 60-second radio ad, questioning the Texas senator’s authenticity and dubbing him a “phony.” The spot comes as the state’s caucuses are just two weeks away, according to Politico.

(Photo by Richard Ellis/Getty Images)

Republican presidential candidate Ted Cruz (Photo by Richard Ellis/Getty Images)

The ad, which will cost $125,000 to run on talk radio, sports and Christian stations beginning on Friday, attacks Cruz on a number of fronts, pointing to a 2012 KERA-TV report that cited Cruz’s allegedly limited charitable giving and his growing salary at the time.

“I also heard he gives less than 1 percent to charity and church,” a voiceover in the ad proclaims, with another individual responding, “He doesn’t tithe? Isn’t he a millionaire? His wife worked for a big Wall Street bank, right?”

Listen to the ad below:

BuzzFeed’s McKay Coppins questioned some of Cruz’s GOP rivals about this very subject this week, with Mike Huckabee seemingly issuing a rebuke of Cruz.

“I just think it’s hard to say God is first in your life if he’s last in your budget. If I can’t trust God with a dime out of each dollar that I earn, then I’m not sure how I can tell him that I trust him with my whole life,” Huckabee said. “To me, it’s a validation of a person’s stewardship and whether they put God first in their life, not just in their political endeavors.”

And he wasn’t done there.

“It’s a matter of authenticity,” Huckabee continued. “If I say I’m a vegan but you look at me eating hamburgers and ribeye every night you’re going to say, ‘I don’t think this guy’s really a vegan.’”

Coppins noted that other candidates, too, have also given very low percentages of their pay to charity, with President Barack Obama reportedly donating just 1 percent of his annual salary in the early 2000s while working at the University of Chicago.

Ted Cruz visits King's Christian Bookstore, Jan. 4, 2016. (Getty Images/Aaron P. Bernstein)

Ted Cruz visits King’s Christian Bookstore, Jan. 4, 2016. (Getty Images/Aaron P. Bernstein)

Past tax records released during Cruz’s Senate candidacy in 2012 found that his income increased quite a bit between 2006 and 2010, moving from $347,716 in adjusted gross income in 2006 to $2,040,840 in 2010, according to KERA-TV.

From 2006 through 2010, records showed $44,000 in charitable giving, though the receiving organizations were not revealed in those documents.

The Cruz campaign has not yet responded to these reports and critiques, and it is unclear whether there might be tithing money that was not included in the 2006 through 2010 data. As is always the case, critics might not truly be presenting the full picture.

The attacks on Cruz come as polls show him and businessman Donald Trump vying for the first-place spot in Iowa just days before the state’s caucuses begin on February 1.

(H/T: BuzzFeed)

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