Donald Trump has shaped the Republican presidential primary in his image.

Regardless of where his candidacy goes from here, his two months of active campaigning have already placed an irrevocable stamp on the nominating process. The businessman has not just determined the issues that his fellow candidates debate but had a suffocating effect on the race, draining attention from all of his rivals.

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The most dramatic effect that Trump’s campaign has had already is to focus the Republican debate on immigration and dramatically shift the Overton Window – the politically viable spectrum of debate – on the issue. While the Republican base had long been opposed to comprehensive immigration reform and doomed any attempt for such legislation to pass on Capitol Hill, Trump has moved the debate dramatically. Where once Republicans contemplated whether it was appropriate for any illegal immigrant to be put on a path to citizenship, they are now focused on the merits of mass deportation and ending birthright citizenship.

Mark Krikorian, the head of the Center for Immigration Studies, a non-profit which seeks to reduce immigration into the United States, said Trump has had “a significant effect” on the discussion and heralded the candidate’s role.

Krikorian said that Trump had had a huge effect on the national conversation with his announcement speech, in which he gave his “usual Trumpist exaggerations” about “Mexico sending all its rapists to the United States”, in combination with the July murder of Kate Steinle, a 33-year-old San Francisco woman who was allegedly shot by an illegal immigrant with seven felony convictions who had previously been deported five times. In his opinion, the confluence of the two has already forced the House of Representatives to pass a bill cracking down on so-called “sanctuary cities”, where city ordinances prevent police from asking about the immigration status of those they arrest, as well as pushed Jeb Bush to harshly condemn them.

Trump’s immigration plan, unveiled on Sunday, has had further impact. It has already led Wisconsin governor Scott Walker to back a push to end “birthright citizenship”, a principle which almost all constitutional scholars think is enshrined in the 14th amendment. Krikorian noted that while Walker had initially staked out “a hawkish position [on immigration] ... he didn’t follow up” until now.

But Trump isn’t just pushing the field to talk about immigration in more strident terms. His presence in the race also changes other topics of debate. Two of the biggest non-Trump political news stories of the summer have been the Obama administration’s controversial nuclear deal with Iran and the emergence of hidden camera videos showing employees of Planned Parenthood discussing the sale of fetal tissue obtained through abortion for medical research. But, as Noah Rothman noted in Commentary last week, both of these issues have been buried by the Trump juggernaut, even though they are of vital concern to the Republican base. After all, these are not comfortable topics of discussion for the formerly pro-choice real estate mogul who gets his military advice from Sunday morning talk shows and they make for far less entertaining stories than Trump’s latest feud with a fellow candidate or television host.

But the rise of Trump to the front of the pack has also frozen the Republican field and prevented many of his rivals from getting their moments in the sun. Since his entry into the race, he has received far more media coverage than any other candidate. The result has meant that with the exceptions of Carly Fiorina, who had a hugely successful performance in the first debate, and John Kasich, who didn’t declare his candidacy until after Trump, every other Republican in the race has flatlined or declined in national polls since Trump’s entry in the race.

His rise to the top has not even yielded any success for candidates with similar views. Rick Santorum, whose emphasis on reducing both legal and illegal immigration and increasing manufacturing jobs makes him perhaps the most similar Republican to Trump (to the extent, of course, that anyone can be like Trump) has continued to poll poorly. Further, fellow outsider Ben Carson has been revived by a strong closing argument at the GOP debate, to inch back up to the same standing he held when Trump first became a candidate.

Ironically, the focus on Trump may help those candidates that he most loathes. The three Republicans long viewed as the most likely standard bearers for their party, Jeb Bush, Marco Rubio and Scott Walker, have been subject to far less scrutiny than would have otherwise been the case.

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In the short term, though, Trump has also whitewashed his reputation among GOP primary voters. The percentage of Republicans who view Trump favorably has dramatically increased during the past few months and unfavorable numbers have declined. While he is still viewed unfavorably by a large swathe of Republican primary voters, opinion of him has swung dramatically in the past few months, with one polling company showing Trump’s approval rating improving by 45 points. And his unfavorable rating dropped from 56% to 35% between April and July. The result is that Trump has established himself as an important figure on the right for the foreseeable future.

It is impossible to predict quite how or even if the Trump phenomenon will end. Every aspect of his campaign has been increasingly unbelievable, from his helicopter to somehow becoming the first Republican ever to pick a fight with Fox News and end up winning. But, regardless of what happens, he has already placed his stamp as firmly on the 2016 Republican primary as he did on the Atlantic City boardwalk.