HARRISBURG — A one-time Democratic power broker in Pennsylvania’s General Assembly was convicted Monday on 10 criminal counts in a corruption trial that focused on a nonprofit he once ran.

The verdict against former House Democratic Whip Mike Veon, who is already serving at least six years in prison for his 2010 conviction in a related case, included eight felony counts that prosecutors said would increase the time he spends behind bars.

“He’s facing significant additional time,” said Deputy Attorney General Laurel Brandstetter, the lead prosecutor in the 11-day trial.

Prosecutors said Veon and a former aide who also was convicted used the state-funded nonprofit — the Beaver Initiative for Growth, or BIG — as a cover for the illegal diversion of taxpayers’ money for Veon’s own personal and political agenda.

Veon, 55, was convicted on six counts of theft, one count each of conspiracy and conflict of interest, and two misdemeanor counts of misapplication of entrusted property. The jury acquitted Veon on five other counts.

Joel Sansone, one of Veon’s lawyers, vowed to appeal.

Jurors convicted Annamarie Perretta-Rosepink, Veon’s codefendant and the former manager of his legislative district office in Beaver Falls, on all six charges against her — three counts of theft and one count each of conspiracy, conflict of interest and misapplication of entrusted property.

All the counts of which Veon and Perretta-Rosepink were convicted involved the use of BIG funds to pay rent on Veon’s legislative district offices in Beaver Falls and Midland or rent on a Pittsburgh office.

A $4,000-a-month retainer that Veon paid to the Harrisburg law firm of his legislative chief of staff, Jeff Foreman, was part of the conspiracy and conflict of interest convictions, but the jury found Veon not guilty on four other counts involving those payments.

Foreman pleaded guilty in the 2010 case as part of a plea deal that required him to testify against Veon and to serve a county jail term.