Controversial business tycoon Donald Trump is no longer the lone top choice as the Republican presidential nominee in the November 2016 US presidential election after last week's debate among the party's presidential hopefuls.

Retired neurosurgeon Ben Carson was able to virtually match Trump's popularity after the debate among possible Republican voters, the latest Rasmussen Reports national telephone survey showed.

According to the survey, 59 percent of likely Republican voters believe that Carson will end up with the party's nomination, with 16 percent considering the retired neurosurgeon as the GOP nominee as "very likely."

In early May, only 25 percent viewed Carson as a possible Republican nominee.

With these significantly improved ratings, Carson is now tied with Trump, who was hammered by his fellow candidates during the debate, as the top Republican presidential hopeful.

Based on the Rasmussen Reports survey, 58 percent of Republican voters consider Trump as their likely presidential nominee for the 2016 elections, with 23 percent considering Trump as the Republican nominee as "very likely."

Aside from Carson, former Hewlett-Packard chief executive officer Carly Fiorina's popularity ratings are also picking up due to her strong performance during Wednesday night's debate.

The Rasmussen Reports poll, conducted on the night of and after the Republican presidential debate, showed that 41 percent of Republican voters see Fiorina as the party's likely nominee.

This figure is a gigantic leap when compared to her ratings in early May, which was just at 16 percent.

Only 9 percent, however, think that Fiorina will very likely be the Republican Party's nominee for the 2016 presidential election.

Former Florida Governor Jeb Bush, meanwhile, garnered the support of 40 percent of the Republican voters who were included in the latest survey.

This number indicates a sharp drop in Bush's ratings after he declared his candidacy in June, when he received support from 56 percent of Republican voters.

The survey was conducted on 1,000 potential US voters by Rasmussen Reports on Sept. 16 to 17. The poll has a margin of error of plus-or-minus 3 percent, with a 95 percent confidence level.