WASHINGTON -- A 13-year campaign to cut the cost of prison phone calls has finally reached a political dial tone, as inmates and their families have found allies in high places.

With prisoners paying as much as $17 for a 15-minute long-distance call, the Federal Communications Commission has formally raised the possibility of new regulations. Potentially, these could range from caps on interstate rates to the elimination of per-call charges.

“It’s a justice issue, it’s a civil liberties issues, it’s an issue of trying to keep families as intact as possible,” FCC Commissioner Mignon Clyburn said in an interview Friday. “This is a situation that cries out for attention.”

Urged on by Clyburn, a South Carolina native and Obama administration appointee, the FCC has opened a two-month public comment period as a possible prelude to new rules. While the companies that provide prison phone service caution against imprudent action, inmates already have been writing their personal pleas.

Pennsylvania inmate Cesar Fernandez Jr. likened prison phone fees to a “theft of money from indigent prisoners and their families.” Washington state inmate Edward L. King, confined at the state’s Monroe Correctional Complex, called the fees “an extortion of millions of dollars a year from those who are traditionally the poorest in our state.”

Aaron Lowers, a 42-year-old prisoner in Vacaville, Calif., advised the FCC that his family members routinely pay about $800 a year on collect-call charges.

“It is difficult enough to maintain familial relationships while incarcerated, having to pay exorbitant rates for short phone calls only makes it more difficult,” he wrote.

Rates differ markedly from state to state. A 15-minute long-distance collect call by a Mississippi inmate costs $14.55, while the same call made by a Texas inmate costs only $6.45, a 2011 Government Accountability Office study found.

A Prison Legal News survey found Georgia inmates paying $17 for a 15-minute call. Underscoring the wide variations, Pennsylvania inmates report their phone costs fell by 70 percent when they were transferred, because of overcrowding, to Michigan.

The fight dates back to 2000, when Martha Wright of Washington, D.C., first sued over the phone rates she was paying to talk to her incarcerated grandson, who was convicted of manslaughter. Wright’s original lawsuit evolved into FCC petitions that languished until now. Wright is now 86 and blind. Her grandson, Ulandis Forte, is now out of prison.

Steven Renderos, national organizer with the Center for Media Justice, explained that numerous prisoner letters already have been solicited because “we felt that the FCC needed to hear from the real victims of the prison telephone industry, the families who have to pay the phone bill.”

But the changes urged on by Clyburn and advocacy groups could face resistance on several fronts.

Some cash-strapped states and facilities collect commissions from prison phone contracts. Texas, for instance, uses some of the money collected for a crime victims’ fund.

Nationwide, states collect more than $150 million a year from prison phone commissions, according to a Prison Legal News survey. These commissions effectively raise call rates, but they also provide funding that states or prisons crave.