WASHINGTON (CNN) Two-thirds of Iowa's Republican voters say they would definitely vote to re-elect Trump if the general election were held today, but nearly as many say the state's party ought to welcome challengers to the President to Iowa's first-in-the-nation caucuses, according to a new CNN/Des Moines Register/Mediacom poll.

The President's strength among the state's registered Republican voters is clear in the poll, with Trump earning an 81% approval rating, a 77% favorability rating, and majorities heralding his choices on immigration, judicial appointments, tax cuts, tariffs and even firing his attorney general as good moves. And by a better than two-to-one margin, Republican voters in Iowa place more blame on congressional Republicans (54%) than on the President (24%) for the party's recent midterm losses.

There is one topic on which Iowa Republicans seem strongly critical of Trump's choices: his use of Twitter. About seven in 10 (72%) say the President has erred by posting potentially inflammatory messages on Twitter on a regular basis. On each other issue position tested in the survey, majorities say the President made a good move.

Overall, 67% of registered Republicans say they would definitely vote to re-elect Trump if the election were held today, 19% would consider someone else and just 10% of the state's Republicans say they would definitely vote for someone else.

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