House Speaker Paul D. Ryan of Wisconsin, left, and Senate Majority Leader Mitch McConnell of Kentucky. (Andrew Harnik/AP)

After his party took full control of Congress 16 months ago, Senate Majority Leader Mitch McConnell (R-Ky.) set a seemingly strange goal for the newly empowered Republicans: Don’t be scary.

The prevailing belief among McConnell and other Republican leaders was that the party was well positioned in 2016 to reclaim the White House and possibly control all the levers of power in Washington — unless conservative back-bench lawmakers on Capitol Hill indulged their worst instincts and scared voters away from the party’s presidential nominee.

Now, Republicans say, the exact opposite might be occurring. Despite some modest success at governance, Republican majorities on Capitol Hill are imperiled because the tone and proposals coming from GOP presidential contenders have terrified independent voters in key battlegrounds.

“It’s a great concern, I think, in a year where all the signs had pointed to Republicans electing a Republican president. Now, all of a sudden, we’re looking at a very, very difficult challenge,” said Sen. Daniel Coats (R-Ind.), who is retiring after two stints in the Senate for 16 combined years.

In a video posted to Facebook and YouTube, Ryan called for "a battle of ideas" in the political realm. (House Speaker Paul Ryan)

Coats thinks that, despite an often ugly process to reach deals with President Obama, congressional Republicans have had their share of success over the past year, which should give incumbents running for reelection something to talk about with voters back home.

Congress approved a new long-term highway funding plan, a permanent fix to a Medicare payment structure for physicians, a two-year budget deal that largely eliminates a chance of a government shutdown, and fast-track authority for trade deals.

It’s exactly the sort of “don’t be scary” agenda that McConnell dreamed of when he finally took control after eight long years as minority leader. Yet, at this point, no one at the Capitol is sure whether the voters can hear them over the din of the presidential campaign, and on both sides of the aisle, anti-establishment figures have railed against Congress.

“The presidential race has hijacked everything that the Congress does or tries to do. It’s clear that Congress has been the target of the candidates,” Coats said.

The louder noise and the greater potential peril are on the Republican side at the moment. Donald Trump and Sen. Ted Cruz (Tex.), who built his anti-establishment credentials by calling McConnell a liar, are the last two Republicans with any real chance of claiming the nomination at the Republican National Convention in Cleveland.

Cruz and Trump have taken a blunt-force approach to their campaigns that is not helpful to the seven Senate Republicans seeking reelection in states that Obama won twice. At least three other Republican-held seats also could be very competitive.

To maintain the majority, McConnell can afford to lose only four seats if the Republican nominee wins the White House, or three if the Democrats hold on to the White House.

Each day the Senate is in session, there’s visible angst among Sens. Kelly Ayotte (R-N.H.), Ron Johnson (R-Wis.), Rob Portman (R-Ohio) and Patrick J. Toomey (R-Pa.) as they walk to votes and face questions about what Trump’s latest controversial proposal or insult means for their reelection chances.

One doesn’t need a stopwatch to know that these senators walk faster than they used to in order to get through the media scrums.

A year ago, their biggest fear was that the hard-right flank in the House would force John A. Boehner (R-Ohio), then the speaker, into another calamitous government shutdown that would doom their reelection chances.

Now, collectively, they would all rather talk about what’s happening on Capitol Hill, even as Democrats try to ratchet up the pressure on McConnell for his refusal to consider Obama’s Supreme Court nomination of Judge Merrick Garland.

The anxiety reached fever pitch in recent weeks as many establishment Republicans eyed the new speaker, Paul D. Ryan (R-Wis.), as someone who should step in at the convention if the delegates deadlocked, believing he could be the white knight who could unify the party and mount a serious challenge to Democratic front-runner Hillary Clinton.

“Paul Ryan would be great for the party and he could certainly win,” Sen. Jeff Flake (R-Ariz.) told reporters Tuesday. Flake said he was one of many GOP insiders who has been pushing Ryan to run for president. But three hours later, Ryan made official what had been painfully clear for many months: He has no interest in trying to navigate the mess.

Instead, Ryan said delegates should choose among those candidates who actually ran for president, which pretty much leaves them with Trump or Cruz. And that doesn’t make many Republicans happy.

Take Sen. Cory Gardner (R-Colo.), a fresh-faced optimist whose 2014 campaign was regarded as the best run of that year. The mainstream conservative spent Monday night mocking Trump on Twitter, questioning how a candidate who can’t understand the Colorado delegate selection process could handle the Islamic State.

In a scrum with reporters last week, Gardner said the other remaining candidate, Ohio Gov. John Kasich, had “no path” to the nomination. He said it was “nonsense” to think Ryan or anyone who had not actually campaigned would be given the nomination.

By process of elimination, this must mean Gardner supports Cruz — but he simply won’t go there, yet. “One of the three will be the nominee,” he said.

Coats, 72, will not be around next year to see firsthand the impact of this election season, but he has enough experience to sense that it will not be easy. He says there are at least five big factions in politics today: three on the Republican side, embodied by Trump, Cruz and Kasich, and two among Democrats, Clinton and Sen. Bernie Sanders (Vt.).

Governance will be painful.

“In my opinion, they’re not going to simply say, ‘Okay, the election’s over, now let’s all get together,’ ” Coats said.

“Those wounds won’t be healed easily, particularly if you’re on the losing side. On the winning side you can probably come together, on the losing side . . .”

His voice trailed off, unwilling to finish the thought.

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