Iowa’s longest-serving Republican legislator, state Rep. Andy McKean, ditched the GOP on Tuesday as he offered a searing renunciation of President Trump, saying he could no longer support Trump as the party’s standard-bearer because of his “unacceptable behavior” and “reckless spending."

McKean revealed he would join the Democratic Party, a decision he described as “very difficult” after spending nearly a half-century as a registered Republican and 26 years in the legislature. But ultimately, he said, “I feel as a Republican that I need to be able to support the standard-bearer of our party.”

And “unfortunately,” he said, he could not bring himself to support Trump.

“Unacceptable behavior should be called out for what it is,” he said during the news conference at the Iowa Statehouse in Des Moines, “and Americans of all parties should insist on something far better in the leader of their country and the free world.”

McKean now joins the ranks of state Republican officials who have fled the party amid a divisive presidency and shifting political landscape. From Kansas to New Jersey, a slow succession of state lawmakers and officials, largely in suburban districts that have become less red, has both startled and appeased constituents by crossing the aisle, oftentimes citing Trump’s rhetoric, policies and a disagreement with their party’s responses to his behavior.

In explaining his decision, McKean said he returned to the Iowa legislature in 2017 after a long hiatus to find the party-line divide more gaping than ever. Upon his return to politics, he felt “increasingly uncomfortable” siding with the GOP on many high-profile issues, he said.

And then there was Trump.

As the 2020 election approaches, McKean said he believed it was “just a matter of time” before the country “pays a heavy price for Trump’s reckless spending and shortsighted financial policies,” as well as his administration’s environmental and “destabilizing” foreign policies.

“He sets, in my opinion, a poor example for the nation and particularly for our children by personally insulting, often in a crude and juvenile fashion, those who disagree with him, being a bully at a time when we’re attempting to discourage bullying,” McKean said.

He continued: “I believe his actions have coarsened political discourse, have resulted in unprecedented divisiveness and have created an atmosphere that is a breeding ground for hateful rhetoric and actions. Some would excuse this behavior as ‘telling it like it is’ and the new normal. If this is the new normal, I want no part of it.”

McKean’s announcement comes as Republicans, lawmakers or otherwise, have grappled with how to respond to the damning portrait of Trump’s presidency presented in special counsel Robert S. Mueller III’s report on Russian interference in the 2016 election. On Tuesday, a member of Trump’s 2016 transition team published an essay in the Atlantic detailing why the report has led him to feel comfortable calling for Trump’s impeachment, even as a longtime Republican.

“I wanted to share my experience transitioning from Trump team member to pragmatist about Trump to advocate for his impeachment, because I think many other Republicans are starting a similar transition,” wrote J.W. Verret, a law professor at George Mason University’s Antonin Scalia Law School who served as deputy director of economic policy for Trump’s transition team until October 2016.

A relatively small number of Republicans began moving toward the Democratic Party after Trump took office. In March 2017, for example, Hawaii state Rep. Beth Fukumoto announced that she was switching to the Democratic Party after the GOP failed to condemn remarks by Trump that she said were racist and sexist. (She has since resigned.) Others, such as longtime GOP operative Steve Schmidt and California Assemblyman Brian Maienschein, left the party citing a disagreement with the Trump administration’s immigration policies, among other things.

In Kansas, four female Republican state lawmakers strengthened the state Democratic Party after defecting in December, in part citing Trump’s degrading comments about women and his “burn-it-all-down attitude” that has turned off women in their district, as state Rep. Stephanie Clayton put it.

State Sen. Barbara Bollier, one of the four lawmakers, told The Washington Post she could no longer “stand up and say, ‘It’s fine to blindly support Trump Republicanism.’"

On the flip side, some Democrats in conservative or rural districts, such as Oklahoma state Rep. Johnny Tadlock, have moved the opposite direction. West Virginia Gov. Jim Justice became a Republican in 2017, just six months after taking office. He announced his decision alongside Trump at one of the president’s rallies.

On Tuesday, while the Democratic Party welcomed McKean, some top Republicans condemned his decision.

Jeff Kaufmann, the state GOP chairman, said McKean “violated the trust of the voters of his district.” McKean represents an eastern Iowa district in Anamosa, near Cedar Rapids.

“It’s disappointing that he felt the need to deceive Iowans,” Kaufmann wrote on Twitter. “If the people of District 58 can’t trust him on something as simple and fundamental as what party he belongs to, how can they trust him on any issue?”

McKean, a retired attorney and square-dance caller, said he anticipated some friends and colleagues would be disappointed. He served in both the Iowa House and Senate from 1979 until 2003, when he left the legislature to spend more time with family. He decided to return to public office for the 2016 election and was ultimately reelected.

Since then, he has voted with the Democrats on numerous occasions, he said Tuesday. Had it not been for Trump, he said he “might have limped along” within the Republican caucus, attempting to do what was best for his constituents.

“However,” he said in closing, “the time comes when you have to be true to yourself and follow the dictates of your conscience. For me, that time has come.”

He said he intends to run for reelection as a Democrat in 2020.

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