Breaking News Emails

Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.
 / Updated  / Source: NBC News
By Perry Bacon Jr.

Ben Carson, the retired neurosurgeon who formally announced his presidential candidacy Monday, is a long-shot to become the Republican nominee. In fact, it’s very unlikely he will win any of the primaries. The big question is how will he impact the campaign.

Carson’s biggest barrier is a lack of experience. He has never held elective office. Americans nearly always vote for a person who has been a vice-president, senator or governor. The last person elected president who hadn’t held one of those offices was Dwight Eisenhower, who won in 1952 after having led U.S. troops in World War II.

Why this such a barrier? Mainly because political parties are reluctant to nominate someone who has not won statewide before.

Carson has almost Eisenhower-like credentials in his field of medicine. He became the head of pediatric neurosurgery at Johns Hopkins, one of the best medical schools in America, at age 33. He drew national attention for an operation to successfully separate conjoined twins. A movie has been made about Carson’s career, and the doctor himself is a best-selling author and popular motivational speaker.

His rise from a low-income neighborhood in Detroit to being one of the top doctors in America was very impressive.

But that experience as doctor did not Carson put at the center of American government and leadership, as Eisenhower was as a general. Colin Powell, another very accomplished African-American who had never held office either before flirting with a presidential run in 1996, had served in top posts in Washington, like national security adviser. And Powell ultimately opted not to run, perhaps understanding the difficulty of aiming for the presidency in his first-ever campaign.

RELATED: Ben Carson Announces 2016 Presidential Run

Despite this lack of government experience, Carson could have been considered a very serious candidate, as Powell was, if had more smartly handled the start of his political career. Carson rose to the attention of conservative activists in 2013 when he used an appearance at the usually staid National Prayer Breakfast to give a forceful speech espousing conservative values. Obama was sitting only a few feet away, and conservatives were delighted with how Carson delivered a blunt dismissal of the president’s policies to his face.

Buzz about a 2016 run for Carson quickly started.

But the surgeon has struggled to follow the informal rules of modern politics in the run-up to his candidacy. He called Obamacare “the worst thing that has happened in this nation since slavery,” leading to criticism he was exaggerating the challenges caused by the health care law. The deeply-religious Carson, 63, has made controversial comments people who are gay, even as most of America shifts toward greater acceptance.

“A lot of people who go into prison go into prison straight – and when they come out, they’re gay. So, did something happen while they were in there? Ask yourself that question,” he said in a CNN interview earlier this year, explaining his view that being gay is a choice.

Nearly all of the major GOP candidates oppose gay marriage, like Carson, but his suggestion that being gay is a choice is unusual.

So as Carson enters the race, he has some support among grassroots conservatives. His backers have organized extensively in Iowa, so Carson has campaign chairs in all 99 of the state’s counties.

But he has virtually no support among Republican elected officials or major elites in the party. More moderate elite Republicans are likely to back Florida Sen. Marco Rubio or ex-Florida governor Jeb Bush.

Conservatives and evangelicals may agree with Carson on policy, but his views are hardly distinct in this race. Republicans who want a candidate who is strongly opposed to same-sex marriage and abortion rights can choose from a number of other hopefuls who both express those views in less controversial ways and have political experience: Texas Sen. Ted Cruz, former Arkansas governor Mike Huckabee and former Pennsylvania Sen. Rick Santorum.

So there is really no plausible path for Carson to win the nomination. If he somehow won the Iowa caucuses, there would be a great effort among Republican elites to make sure he did not win other states.

Carson no doubt knows this. So what will be interesting to watch is how he attempts to shape the GOP process. Past long-shot black GOP presidential candidates like Alan Keyes (1996, 2000) and Herman Cain (2012) added little, using the campaign to raise their fame instead of pushing forward new ideas or challenging other candidates in the presidential debates.

Carson has some unique credentials to offer, if he chooses. As a doctor, he could articulate concrete steps to change Obamacare and improve America’s health care system. As a social conservative with little chance of winning, he could be the spokesman during the campaign for older, religious voters who passionately oppose same-sex marriage and broader expansions of gay rights. That role would be significant, with the U.S. Supreme Court likely to outlaw gay marriage bans in the midst of this campaign.