U.S. Sen. Pat Roberts has defeated tea party-backed challenger Milton Wolf in Kansas’ Republican primary.

The results Tuesday dealt a blow to a national tea party movement that’s targeted longtime Washington incumbents.

Two lesser-known candidates trailed Roberts and Wolf in the race for the GOP nomination in the conservative state.

Roberts is expected to win his fourth, six-year term and extend a career in politics that dates back to the late 1960s, when he was a congressional aide.

Wolf is a 43-year-old Leawood radiologist who was making his first run for public office. He called the 78-year-old Roberts an out-of-touch career politician.

But Roberts had a far better-funded campaign and attacked Wolf over questionable postings of graphic X-ray images on a personal Facebook page in 2010.