Republican senators heaped praise on Sen. Orrin Hatch for his four decades in the upper chamber after he announced his plan to retire at the end of 2018.

Hatch made the highly anticipated announcement about his future in a video to supporters published Tuesday.

“Every good fighter knows when to hang up the gloves,” the senator said. “For me, that is soon approaching.”

Hatch, the current chairman of the Senate Finance Committee, will end his career having served seven terms in the Senate, and his retirement opens the door for Mitt Romney, the 2012 Republican presidential nominee, to run for his seat.

Following Hatch’s announcement, many of Hatch’s fellow Republicans thanked the Utah senator for his service and work over his career.

“It has been an honor to work with you on Finance Committee Chairman Hatch. Thank you for your service to Utah and our nation!” Sen. Tim Scott, R-S.C., tweeted.

“Passing of an era,” Sen. John Cornyn, R-Texas, tweeted. “Great man.”

Sen. Thom Tillis, R-N.C., praised Hatch for his years in the Senate, and Sen. Chuck Grassley, R-Iowa, reflected on the time he spent working with Hatch.

“It’s been an honor to work with you, especially on the SUCCEED Act. Thank you for your service to our nation!’ said Sen. Thom Tillis, R-N.C.

“Sen Hatch is a friend for 37 yrs while serving together in US Senate. He serves Utah & USA w tremendous success as effective as can be & deserves credit 4 doing so,” Grassley said on Twitter.

Sen. Jeff Flake, R-Ariz., who also announced his own decision not to seek re-election this year, commended Hatch for his commitment to the people of Utah and conservative principles.

"For more than 40 years @OrrinHatch has faithfully and effectively represented Utah and promoted conservative principles in the U.S. Senate. Thankful for his service and proud to call him a colleague and a friend," Flake tweeted.

Republican Sen. Mike Lee, Hatch's fellow Utah senator, said he was optimistic Hatch would continue to help Utah residents, and Utah Gov. Gary Herbert, a Republican, praised Hatch's "strength and dignity."

"Sen. Hatch has been a tremendous servant to the people of Utah and he will be sorely missed. It has truly been an honor serving with him in the United States Senate and I know he will continue to do fantastic work for Utahns," Lee tweeted.

"Few have been as dedicated to serving the people of Utah as our good Senator, Orrin Hatch. For seven terms, he has represented the people of Utah with strength and dignity. We are grateful for his hard work and for his untiring effort on behalf of our state. I wish him the best," Herbert said on Twitter.