Egomaniacal Donald Trump suddenly finds an unexpected rival nipping at his heels: retired neurosurgeon Dr. Ben Carson. According to the latest New York Times/CBS News Poll, Carson’s popularity among GOP voters has jumped a whopping 17% over the past six weeks, while Trump’s has risen only 3%. The Trumpster still holds a four-point lead over Carson (27% to 23%). However, considering that other major GOP candidates’ poll numbers have been sliding precipitously and remain in the single-digit range, this news does not bode well for the Trump campaign.

These poll numbers come on the eve of the second GOP debate, to be held Wednesday, September 16th. At the moment, slightly more the half of Trump’s supporters are committed to their chosen candidate – while the rest say they could still be convinced to change their votes.

At $10 million, Ben Carson’s own personal financial resources are a mere fraction of Trump’s reported net worth of $10 billion. However, when it comes to raising funds from political donors, Carson thoroughly trounces Trump by nearly 9 to 1. So far, Carson’s campaign contributions come to $10.8 million, about two-thirds of which comes from small donors. Trump has received less than $2 million – mostly in the form of candidate loans.

On many issues, Carson and Trump hold similar views. Both oppose a woman’s right to choose, affirmative action, and same-sex marriage, and believe in keeping “God in the public sphere.” Both candidates support unrestricted gun ownership and school vouchers, and are against any expansion of the Affordable Care Act. The two candidates have similar positions on defense and military issues (though neither has actually served).

However, they part ways on environmental issues. Neither candidate supports renewable energy, but Carson believes that EPA regulations could be strengthened, while Trump would like to see environmental protections dismantled altogether. They also differ over one of the hot-button issues of this election: higher taxes on the wealthy. Trump, whether he’s seeing the handwriting on the wall with Bernie Sanders or has had a genuine “Come to Jesus moment,” supports tax increases for the 2% of top income earners. Carson does not.

Considering that conservatives continue to cling to the discredited idea that the wealthy shouldn’t be taxed because they are somehow “job creators”, Carson could very well hold an edge over Trump. It is also possible – and even likely – that Donald Trump’s outrageous antics and asinine statements are wearing thin among voters. Carson may be on the wrong side of history, but his discourse has been more reasoned.

Last month, GOP Arizona senator Jeff Flake described Trump’s campaign as “laughable”, despite the business mogul’s growing support among the Republican rank-and-file. The fact is that the game is still in its early stages. Trump still has momentum, but it’s slowing. Meanwhile, Carson appears to be coming up behind him and closing in fast.