Only 30 percent of Republican aides to members of Congress who responded to CQ Roll Call’s Capitol Insiders Survey say they will vote for Donald Trump if he is the GOP candidate for president.  

Slightly more than half of the GOP respondents to the March poll said they would not vote for a man who has turned Republican orthodoxy on its head on issues ranging from trade to taxes and is widely seen as a demagogue.  

The online survey, which was emailed to aides on March 16, was open through March 22. It drew responses from 295 aides, 157 of whom said they were Republicans and 130 Democrats.  

The Republican staffers are more candid than their bosses.  

Despite widespread discontent about Trump, Ben Sasse of Nebraska is the only Republican senator so far to say he will not vote for him. In the House, too, few lawmakers have said publicly they won’t support Trump if he is the GOP primary voters’ choice. They include Justin Amash of Michigan, Carlos Curbelo of Florida, Robert J. Dold of Illinois, Richard Hanna of New York, Reid Ribble of Wisconsin, Scott Rigell of Virginia and Mark Sanford of South Carolina.  

Even so, plenty are criticizing the Republican front-runner and the level of opposition to Trump from the party elite, staffers and lawmakers, indicates that the businessman is causing dismay in the GOP establishment.  

“I don’t think he should be our nominee,” said Jeff Flake , the Republican senator from Arizona, who had endorsed Sen. Marco Rubio .  

Others are denying the obvious in the hopes of holding the party together. Earlier this month, all three of Trump’s opponents at the time — Rubio, Sen. Ted Cruz  and Ohio Gov. John Kasich — said during a Fox News debate they would support the nominee, whoever it is.  

Some other prominent Republicans — such as former Senate leader and presidential nominee Robert Dole  — have even argued that the party would be better off with Trump than with his chief competition in the primary race, Cruz, the Texas lawmaker who has alienated colleagues with his uncompromising, hard-right politics.

But the GOP aides who responded to CQ Roll Call’s survey said they preferred Cruz to Trump by a 2-to-1 margin.

A solid majority of GOP aides who filled out the survey, 62 percent, now say a contested Republican convention is likely. Perhaps that’s wishful thinking, since it would give Cruz or Kasich a shot at the nomination. But the staffers are also feeling resigned. A majority of respondents in past months consistently said they expected Rubio to win the nomination and hoped he would. With him out of the race, 61 percent of the GOP aides now say it will be Trump.  

Democratic lawmakers say Trump could be a tough opponent in November. “People have been underestimating his campaign for nearly a year, and it’s time to wake up,” Massachusetts Sen. Elizabeth Warren warned on her Facebook page this week.  

She might have addressed the warning to Democratic staffers on Capitol Hill. The prospect of a Trump candidacy has them licking their chops. Sixty-two percent of the Democratic aides who responded to the survey said that if it’s Trump vs. Hillary Clinton in the general election, Clinton would win in a landslide. Another 36 percent expect her to win narrowly. Only 2.4 percent said they thought Trump would eke out a win.  

Asked who is the most formidable of the remaining Republican candidates, the Democratic aides said Kasich. Fifty-nine percent rated the former House Budget Committee chairman as their toughest potential competition. Twenty-six percent said Trump. Only 6 percent said it would be Cruz.  

If GOP aides are worried about Trump, they’re also concerned about the Republican strategy on the Supreme Court vacancy. In response to a survey question about the political ramifications of Senate Majority Leader Mitch McConnell ’s decision not to even hold a vote on President Barack Obama’s nominee, federal appeals Judge Merrick Garland, 39 percent said the Kentucky Republican’s approach would benefit the Democrats in November. Only 26 percent think it would help the GOP.  

That seemed clear last week when the most embattled Republican senator facing re-election, Mark S. Kirk , said McConnell should bring the Garland nomination to the floor. The Illinois senator criticized “the partisanship and political rancor that too often consumes Washington” and said his colleagues should “man up” and vote.  

The Democratic aides who responded to the survey, by contrast, are convinced that McConnell’s intransigence will work to their advantage. Ninety-four percent of them said the Democrats will benefit on Election Day.  

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