While presidential candidates are vying for votes in what figures to be a close set of Iowa caucuses, a recent poll gives a picture of who Pennsylvania voters prefer.

Hillary Clinton and Donald Trump are the favorites of their respective parties in the Keystone State, according to a survey from Franklin & Marshall College released Thursday.

While Clinton's main challenger, Vermont Senator Bernie Sanders, has closed the gap among the state's Democratic voters in the poll, Trump has separated himself from the GOP pack.

Clinton leads Sanders with 46 percent to his 29 percent. That's an improvement from October for Sanders, who trailed Clinton in an October poll from the college with 18 percent to Clinton's 52 percent.

Trump, meanwhile, has pulled away from his rivals in Pennsylvania. He leads a crowded group with 24 percent, with the closest challenger being Texas Senator Ted Cruz (14 percent). Florida Senator Marco Rubio was third with 11 percent.

In October, Trump was neck-and-neck with retired neurosurgeon Ben Carson, leading him by a single percentage point. In the latest poll, Carson came in fourth with 5 percent.

The poll also found that terrorism is the most important issue for the state's Republicans when weighing their choice for president (26 percent), while unemployment was the biggest issue for Democrats (17 percent).

Governor Tom Wolf's approval rating has dipped since October, the poll found, with only one in three saying he was doing an "excellent" or "good" job, a drop from 36 percent.

However, more residents blamed the GOP-controlled state legislature for the ongoing budget impasse than Wolf.

The poll surveyed 732 registered Pennsylvania voters from Jan. 18-23. It had a margin of error of 3.6 percentage points.