DES MOINES, Iowa (AP) — A federal court has rejected the sentencing appeal of former Iowa Sen. Kent Sorenson, who is serving a 15-month federal prison sentence for causing false campaign finance reports to be filed and obstructing an investigation.

Sorenson accepted money for endorsing presidential candidate Ron Paul in 2012 but was caught up in a criminal case when federal authorities said he and Paul campaign officials attempted to hide the payments.

He pleaded guilty and expected probation but was given prison time in January when Judge Robert Pratt concluded Sorenson betrayed the public trust and deserved punishment.

He appealed the sentence but the 8th U.S. Circuit Court of Appeals on Tuesday concluded Pratt's sentence was appropriate.

Sorenson is at a minimum security prison in Thomson, Illinois. He is due for release in April.