The 2018 midterm elections are only months away, and members of Congress -- Republicans in particular -- are ready for a career change.

So far, more than 30 Republicans in the House and Senate have announced that they plan to leave Congress by the beginning of 2019. Far fewer Democrats have announced plans to leave office.

Why are so many Republicans retiring?

Some of the retiring GOP lawmakers have served in Congress for several decades: Rep. Sam Johnson, R-Texas, who first joined the House in 1991; Rep. Ileana Ros-Lehtinen, R-Florida, who first arrived at Capitol Hill in 1989; Rep. John Duncan, R-Tennessee, who was first sworn in in 1988; and Sen. Orrin Hatch, R-Utah, who first entered the Senate in 1977. Others are somewhat newer to politics and have decided to return to the private sector, citing their desire to spend more time with family. A few aspire to statewide office and are running for Senate or governor, taking President Trump's rise as their inspiration.

Others have opted not even to wait until the end of their terms to tender their resignation -- including Reps. Jason Chaffetz of Utah, Embattled GOP Rep. Tim Murphy to resign from House of Pennsylvania and Trent Franks of Arizona. Chaffetz served as chairman of the House Oversight and Government Reform Committee and has since gone on to work for Fox News. Murphy resigned from Congress after details of an extramarital affair became public. A day before his resignation, he had announced he had plans to retire and a report had revealed that text messages suggested Murphy urged a woman with whom he was having an affair to have an abortion even though he has long advocated an anti-abortion stance. Franks announced his departure after it was reported he offered a former staffer millions of dollars to have his child.

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Of the Republicans planning to leave Congress in early 2019, a number hold committee chairmanships. Rep. Jeb Hensarling, R-Texas, chairman of the House Financial Services Committee, announced he won't seek re-election after serving in the lower chamber since 2003.

"Today I am announcing that I will not seek reelection to the U.S. Congress in 2018. Although service in Congress remains the greatest privilege of my life, I never intended to make it a lifetime commitment, and I have already stayed far longer than I had originally planned," the Texas Republican said in a note to supporters.

Rep. Diane Black, R-Tennessee, chairwoman of the House Budget Committee who took over the gavel from Tom Price when he was confirmed as Health and Human Services Secretary -- he has since resigned -- announced in August that she plans to run for governor of her state next year.

Fellow Tennessean, Sen. Bob Corker, became the first Republican in the upper chamber to announce plans to retire in early 2019. He serves as chairman of the Senate Foreign Relations Committee and has played a pivotal role in negotiations over bipartisan sanctions targeting Russia, among other pieces of legislation.

"When I ran for the Senate in 2006, I told people that I couldn't imagine serving for more than two terms," Corker said in a statement in late September. "Understandably, as we have gained influence, that decision has become more difficult. But I have always been drawn to the citizen legislator model, and while I realize it is not for everyone, I believe with the kind of service I provide, it is the right one for me."

Rep. Bob Goodlatte, chairman of the House Judiciary Committee, also will not be seeking reelection.

Rep. Darrell Issa, R-Calif., a former chairman of the House Oversight and Government Reform Committee and the richest member of the House, announced in January he would be leaving Congress after the end of his ninth term.

Rep. Trey Gowdy, R-South Carolina, announced at the end of January that he will retire at the end of the year. Gowdy became the chairman of the House Oversight and Government Reform Committee last June after Rep. Jason Chaffetz, R-Utah, decided to resign from Congress.

While most have been more coy about their decisions to ultimately step down, some are pointing to the divisive political environment that has only flourished and grown more partisan under President Trump.

Sen. Jeff Flake, R-Arizona, shocked the political world not long after Flake, with his announcement to retire and his decision to speak out against the president.

The Arizona Republican announced on the Senate floor in October that he could "better serve my country and conscience" by dropping his re-election bid, "freeing myself of the political consideration that consumed far too much bandwidth," he said. Flake issued a thinly-veiled take-down of President Trump, criticizing the "personal attacks," the "threats against principles, freedom and institutions" and "flagrant disregard for truth and decency." He argued that recklessness, outrageous and unhinged behavior have been excused as "telling it like it is, but he warned that when such behavior "emanates from the top of government," he said it's something else.

"It is dangerous to our democracy," Flake said. "Why didn't you speak up? What are we going to say?" he asked rhetorically. "Mr. President, I rise today to say, enough."

Rep. Charlie Dent, R-Pennsylvania, announced in early September that he won't seek re-election. He served as a co-chair of the moderate Tuesday Group in the House. In the statement revealing his decision, Dent referenced the dysfunction in Washington.

"As a member of the governing wing of the Republican Party, I've worked to instill stability, certainty and predictability in Washington. I've fought to fulfill the basic functions of Government, like keeping the lights on and preventing default," he said. "Regrettably, that has not been easy given the disruptive outside influences that profit from increased polarization and ideological rigidity that leads to dysfunction, disorder and chaos. But I have also had a stake in major legislative accomplishments: budget agreements that prioritize our federal commitments, pro-growth trade and tax policy, initiatives to advance medical innovation and research, major infrastructure investments, and policies that secure our homeland."

As of Jan. 31, 2018, there are 38 Republican House members who are not returning to the House for another term.

Republicans retiring in 2018:

Retiring Senate Republicans

Sen. Bob Corker, R-Tennessee Sen. Jeff Flake, R-Arizona Sen. Orrin Hatch, R-Utah



Retiring House Republicans

Rep. Joe Barton, R-Texas Rep. John Duncan, R-Tennessee Rep. Blake Farenthold, R-Texas Rep. Rodney P. Frelinghuysen, R-New Jersey Rep. Bob Goodlatte, R-Virginia Rep. Trey Gowdy, R-South Carolina Rep. Gregg Harper, R-Mississippi Rep. Jeb Hensarling, R-Texas Rep. Darrell Issa, R-California Rep. Lynn Jenkins, R-Kansas Rep. Sam Johnson, R-Texas Rep. Frank LoBiondo, R-New Jersey

Rep. Ted Poe, R-Texas Rep. Dave Reichert, R-Washington Rep. Ileana Ros-Lehtinen, R-Florida Rep. Ed Royce, R-California

Rep. Bill Shuster, R-Pennsylvania Rep. Lamar Smith, R-Texas Rep. Dave Trott, R-Michigan Rep. Tom Rooney, R-Florida Rep. Ryan Costello, R-Pennsylvania Rep. Paul Ryan, R-Wisconsin Rep. Dennis Ross, R-Florida Rep. Tom Garrett, R-Virginia

House Republicans who have resigned or will resign

Rep. Jason Chaffetz, R-Utah Rep. Trent Franks, R-Arizona Rep. Patrick Meehan, R-Pennsylvania

Rep. Tim Murphy, R-Pennsylvania Rep. Pat Tiberi, R-Ohio Rep. Charlie Dent, R-Pennsylvania

House Republicans running for another office

Senate:

Rep. Lou Barletta, R-Pennsylvania Rep. Marsha Blackburn, R-Tennessee Rep. Evan Jenkins, R-West Virginia Rep. Luke Messer, R-Indiana Rep. Todd Rokita, R-Indiana Rep. Martha McSally, R-Arizona



Governor:

Rep. Diane Black, R-Tennessee Rep. Raul Labrador, R-Idaho Rep. Kristi Noem, R-South Dakota Rep. James Renacci, R-Ohio Rep. Steve Pearce, R-New Mexico Rep. Ron DeSantis, R-Florida

Other:

Rep. Jim Bridenstine, R-Oklahoma (nominated for NASA Administrator)



— Kathryn Watson contributed to this report.