(CNN) If the election for President were held today, only 36% of likely 2018 voters said that they would definitely vote to re-elect Donald Trump, according to a new poll by Grinnell College released Wednesday. More -- 43% -- say they would definitely vote for someone other than Trump, and another 17% said they'd consider it.

Nearly three-quarters of Republicans and Republican-leaning independents plan to definitely vote for Trump (72%), with 18% who said they'll consider someone else. That's below the 84% in that group who say they approve of his work as President. Eight-in-10 Democrats would definitely vote to elect someone else with almost half of independents agreeing at 47%. The rest of the independents are split between considering someone else (23%) and definitely voting for Trump (26%).

The poll differs from other recent polls on this fall's election, however, with only 45% who said they'd vote for a Democratic candidate in the November election and 43% who said they'd support a Republican. Other polls with similar methodologies have shown anywhere from an eight-point advantage for Democrats to a 14-point advantage

According to the poll, about four-in-ten approve of the job Trump is doing as President and half disapprove. A new CNN Poll of Polls shows that across the five most recent polls conducted using live telephone interviews of adults or registered voters, Trump's approval rating averages 40%, with 54% saying they disapprove.