GOP presidential candidate Donald Trump holds a commanding lead among Idaho Republicans; a new Idaho Politics Weekly poll shows.

As the GOP race tightens in early-voting states, like Iowa and New Hampshire, Trump has few concerns in Idaho, where Republicans hold a closed primary on March 8.

The Dan Jones & Associates poll finds Trump is preferred by 30 percent of Idaho Republicans.

Retired doctor Ben Carson – who has been fading fast in other states – comes in second with 19 percent support; followed by Texas Sen. Ted Cruz at 16 percent; and Florida Sen. Marco Rubio at 10 percent.

All the other candidates are in single digit support, Jones finds.

And 10 percent of Idaho Republicans didn’t have a favorite yet.

Idaho’s presidential primary is on March 8, one week after the Super Tuesday primaries in many states.

Of course, a lot will change by March 8. Most of the current GOP candidates will be out of the race by then, narrowing the field.

Mormons make up a significant bloc of Idaho voters, especially in the south of the state.

In Utah – home of the LDS Church – Trump is doing poorly, partly because of editorials by the church’s newspaper, the Deseret News, and church leader statements against Trump’s views on stopping Muslim immigration and visitations.

But that word hasn’t reached all the Idaho Mormons, apparently. Jones finds that Trump leads among Idaho Mormons with 17 percent of the vote; Carson and Cruz are tied at 16 percent; with Rubio getting 11 percent support.

In the Democratic race for president, among her party members, Hillary Clinton remains the front-runner. But not by much.

Jones finds that she has 44 percent support among Idaho Democrats, Vermont Sen. Bernie Sanders has 41 percent support, and former Maryland Gov. Martin O’Malley has 3 percent support. Ten percent of Idaho Democrats don’t yet have a favorite.

Independents can also vote in the Democratic primary. And there Sanders leads Clinton, 36-20 percent, with 23 percent undecided.

By March 8 Clinton will likely either have the nomination sewed up, or she will be in considerable trouble with Sanders dogging her campaign.

Idaho is a very Republican state, with GOP officeholders in all the major federal and state offices.

Accordingly, Clinton loses in statewide match-ups with each of the GOP presidential candidates Jones paired her with in his latest survey.

Clinton loses to Carson, 23-45 percent; to Trump, 25-45 percent; to former Florida Gov. Jeb Bush, 24-42 percent; and to Cruz, 24-46 percent.

Finally, Jones asked whether the presidential debates are worthwhile and what are the most important factors in Idahoans’ presidential picks.

Sixty-eight percent said the debates are good, 30 percent said they are not worthwhile to them.

And in a long list of possible reasons to support a presidential candidate, 16 percent of Idahoans said their top concern is terrorism/national security; 15 percent said the economy; and 33 percent mentioned some other topic not listed.

All the other topics fell into the low single digits as mattering to Idahoans.

Jones polled 604 adults from Dec. 17-29, with a margin of error of plus or minus 3.99 percent.