AUSTIN (CBSDFW.COM/AP) — The former physician to President Donald Trump, whose Department of Veteran Affairs nomination was derailed by professional misconduct allegations, has filed paperwork to run for a rural Texas congressional seat.

Former Navy Rear Adm. Ronny Jackson joins a crowded field of Republican hopefuls running to replace Rep. Mac Thornberry, who isn’t seeking reelection after 25 years in Congress. Jackson filed his candidate paperwork on Monday’s deadline in Texas to get on the ballot.

Jackson had worked as White House physician since 2006. He had declared Trump in excellent health and was a surprise choice last year for secretary of Veterans Affairs, but his nomination unraveled over allegations of drinking on the job and over-prescribing drugs.

Jackson called the allegations “completely false and fabricated” but ultimately withdrew his name from consideration for the post.

Trump had been impressed with Jackson’s performance, telling aides that he liked Jackson’s smooth turn before the cameras and ability to field reporters’ questions as he offered a glowing report on the president’s physical and mental well-being. During one extraordinary briefing with reporters, Jackson extolled Trump’s “incredible genes” and joked that he might have lived to be 200 years old if he had eaten healthier.

Thornberry, a former chairman of the Armed Services Committee, is one of six House Republicans in Texas who are retiring next year. His district that runs through the Texas Panhandle is safely Republican. Jackson is a native of Levelland, which is near Lubbock although just outside of Thornberry’s district.

Jackson, a Texas A&M grad, attended medical school at the University of Texas Medical Branch. He graduated in 1995.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)