WASHINGTON -- U.S. Rep. Rodney Frelinghuysen, both the most powerful and endangered member of the New Jersey congressional delegation, announced Monday that he would not seek re-election at the end of his 12th term in the House of Representatives.

Frelinghuysen, R-11th Dist., gave no reason for retiring. He joins Rep. Frank LoBiondo, R-2nd Dist., as New Jersey lawmakers retiring at the end of the year. Both were elected in the Republican landslide of 1994.

He became House Appropriations Committee chairman in 2017, giving him power over all spending bills. He used the position to insert $900 million into House legislation for the Gateway tunnel project.

At the same time, he faced his toughest re-election campaign, in part due to opposition to Trump. The Cook Political Report, a Washington-based publication that tracks congressional races, rates the race a toss-up.

Several Republican state officials have been mentioned as potential replacementa for Frelinghuysen, including state Sen. Joseph Pennachio, R-Morris, and Assemblyman Anthony Bucco, R-Morris.

"I want to speak to my wife and have a little time to digest and make some phone calls and see what kind of support I have." said Pennachio, an early supporter of Trump.

Bucco said he had received some calls about running.

"I'm weighing my options," he said. "I think you have to do that whenever an opportunity is presented to you. You have to make a smart decision."

Frelinghuysen, 71, announced his retirement with a call for bipartisanship, something that was lacking in the last session of Congress when Republicans used parliamentary maneuvers to tackle both health care and taxes without the need for Democratic votes.

Frelinghuysen voted for both resolutions that allowed Senate Republicans to prevent Democratic filibusters.

"I have worked in a bipartisan manner, not just in times of crisis but always, because I believe it best serves my constituents, my state and our country," Frelinghuysen said.

"My father reminded me often that we are temporary stewards of the public trust. I have sincerely endeavored to earn that trust every day and I thank my constituents and my home state of New Jersey for the honor to serve and I will continue to do so to the best of my abilities through the end of my term," he said.

His service in Washington drew praise from politicians of both parties.

"Public service runs deep in the Frelinghuysen family and, while we have not always agreed on the issues, Rodney has always been a dedicated public servant who has stood by his convictions," Gov. Phil Murphy said.

Congratulations on 24 yrs of exemplary service to our state and the nation @USRepRodney. I am proud to have worked with you and proud to be your constituent. You will be missed by so many who have benefitted from your wise leadership at the county, state and national level. — Governor Christie (@GovChristie) January 29, 2018

Thank you @USRepRodney for your many years of service on behalf of the people of New Jersey. I wish you and your family nothing but the best in the years ahead. pic.twitter.com/hcuBL2AEpd — Bill Pascrell, Jr. (@BillPascrell) January 29, 2018

"Serving in the armed forces during Vietnam, as a representative in the state legislature, and as a congressman, I commend his service and that of his family to our great state and our nation since its founding," said state Sen. Richard J. Codey, D-Essex, a former governor. "He has been a friend not only to me but to thousands of New Jerseyans."

Rep. Chris Smith, the dean of the state's congressional delegation, credited Frelinghuysen with helping to protect the New Jersey Highlands, an importat source of drinking water.

"Continuing a family tradition of public service that dates back to the founding of the country, he has been especially influential in serving citizens of New Jersey through the aftermath of the 9/11 attacks and after the destruction of Hurricane Sandy, ensuring that residents were properly supported by the federal government in their greatest hours of need," said Smith, R-4th Dist.

Frelinghuysen bucked his party and voted against the Republican tax bill that gutted the federal deduction for state and local taxes, but supported the health care bill that the Congressional Budget Office said would leave 23 million more Americans without coverage.

While Trump signed the tax bill into law, the effort to repeal the Affordable Care Act failed in the Senate.

Democratic Congressional Campaign Committee spokesman Evan Lukaske said Frelinghuysen's retirement was "no surprise given his community's disgust with this Republican Congress, which spent nearly all of last year throwing our health care system into chaos and ended it by increasing taxes on thousands of hardworking New Jersey families."

Rep. Steve Stivers, R-Ohio, chairman of the National Republican Congressional Committee, said he expected the district to remain in GOP hands.

"Congressman Frelinghuysen's record of service to New Jersey's 11th district will be remembered for decades to come," Stivers said. "We'll sorely miss his leadership in Congress and I wish him well in the next chapter of his life. This district has been held by a Republican since the 1980s, and we plan to keep it that way in November."

Frelinghuysen's retirement could mean the end a political dynasty that predates the founding of the United States. His father once represented the district he now serves. There were Frelinghuysens in the U.S. Senate and on the 1844 Whig Party ticket as Henry Clay's vice-presidential nominee.

He used his retirement announcement to "strongly encourage" the next generation to enter public service.

"Public service is an incredible way to turn your convictions into something that serves the greater good and to do it alongside people from every walk of life and background," Frelinghuysen said.

NJ Advance Media staff writer Brent Johnson contributed to this report.

Jonathan D. Salant may be reached at jsalant@njadvancemedia.com. Follow him on Twitter @JDSalant or on Facebook. Find NJ.com Politics on Facebook.