Valley View High School football senior Nyeem Wartman embraces his mother, Veronica White, after signing his letter of intent Wednesday to attend Penn State.

STATE COLLEGE — New Penn State coach Bill O’Brien gave credit to the recruits who stuck with their verbal commitments to the Nittany Lions.

It would have been easy for them to join the roughly half-dozen prospects that left for other schools in light of the upheaval surrounding the football program since November.

Instead, just more than half of Penn State’s 19-member recruiting class is comprised of holdovers who initially committed to O’Brien’s predecessor, the late Hall of Fame coach Joe Paterno — a foundation that O’Brien said allowed the new regime to target fresh prospects who were the “right fit” for Happy Valley.

“That was a real testament to their mental toughness and their ability to stick it out,” O’Brien said in a conference call Wednesday with reporters. “I give them all the credit in the world. I can’t wait to start coaching and working with them.”

As of Wednesday night, recruiting services had Penn State’s 2012 class ranked anywhere from 39th to 50th in the country and middle of the pack in the Big Ten.

Most of the class won’t get to campus until June. Even O’Brien isn’t at Penn State full time yet either, having to split loyalties while he finishes up his other job as offensive coordinator for the New England Patriots.

O’Brien was hired Jan. 6. He plans to settle full-time in State College starting Tuesday, whether or not the Patriots beat the New York Giants in the Super Bowl on Sunday.

Until then, he hasn’t been able to devote his full attention to Penn State — which is why O’Brien heaped praise on his assistants for taking the lead on piecing together the recruiting class. In particular, O’Brien singled out defensive line coach Larry Johnson, a top-notch recruiter and returnee from Paterno’s staff.

“It was a very seamless transition,” O’Brien said.

But they had to recruit under conditions unlike any other program in the country.

The arrest of retired defensive coordinator Jerry Sandusky on Nov. 5 on dozens of child sex abuse charges set in motion a scandal that led to university trustees ousting Paterno four days later. The NCAA and Big Ten are also looking into how the school handled the allegations.

Awaiting trial, Sandusky is out on bail after denying the allegations. Paterno was a witness before a state grand jury investigating Sandusky, and authorities said he was not a target of the probe.

O’Brien and his staff have stressed they will build on the “traditions of academics and athletics.”