LITTLE ROCK, ARK. — Sen. Mark PryorMark Lunsford PryorMedicaid rollback looms for GOP senators in 2020 Cotton pitches anti-Democrat message to SC delegation Ex-Sen. Kay Hagan joins lobby firm MORE (D-Ark.) on Friday accused House Republicans of trying to "undermine the integrity" Medicare and Social Security, implicitly accusing his Senate opponent of wanting to drastically change the popular programs.

"When I look at Republicans, especially on the House side, what I see is a group of House members that are persistent in trying to … undermine the integrity of Medicare and Social Security," said Pryor, who was speaking to a conference of optometrists in a hotel next door to Arkansas's old statehouse.

"Basically, they're coming after Medicare and Social Security. I think it's bad policy, I think it's bad for Arkansas," the senator followed up.

Pryor is facing a tough challenge from Rep. Tom CottonTom CottonMcCarthy: ‘No deadline on DACA’ DHS chief takes heat over Trump furor Lawmakers see shutdown’s odds rising MORE (R-Ark.). He's made protecting the programs — and Cotton's vote for Rep. Paul RyanPaul Davis RyanGOP leaders pitch children's health funding in plan to avert shutdown Lawmakers see shutdown’s odds rising Fix what we’ve got and make Medicare right this year MORE's (R-Wis.) budget that would make major changes to Medicare — a central part of his campaign. The programs are particularly important in Arkansas, a poorer state where many seniors are dependent on them.

The two-term senator spent much of the rest of his speech talking up bipartisanship and arguing that he was one of the few in Washington who was trying to work across the aisle.

"Ever since I've been up there, I've tried to work in a very bipartisan way. In fact, some of my colleagues, they call me Mr. Bipartisanship," he said before invoking the Bible to knock the "my way or the highway" approach he said many in both parties followed.

"That's not going to get us anywhere," he said. "I'm not in that camp. I'm in the Isiah camp: 'Come, let us reason together.' Let's sit down, let's work through this, let's try to work things out."

Pryor received a standing ovation from the nonpartisan group.

Afterward, he showed flashes of why he's still in the race despite Arkansas's heavy Republican lean in federal races. Pryor has led Cotton in most recent polling.

A constituent came up to Pryor to complain about President Obama, ObamaCare and Benghazi. While he was fiercely critical of the president he nodded intently when Pryor blamed "partisan gridlock" for freeing Obama's hand on some recent executive orders because Congress couldn't compromise on anything.

"I think you'll hear more about Benghazi as we go through this next year," Pryor said when asked about the lightning-rod issue.

The man, who said he was a veteran, agreed with Pryor when said he'd long fought for a strong military, shaking his hand as he left.