SACRAMENTO/WASHINGTON (Reuters) - Republican state senators in California gathered in Sacramento late last month for what amounted to an intervention.

U.S. Democratic congressional candidate Conor Lamb speaks during his election night rally in Pennsylvania's 18th U.S. Congressional district special election against Republican candidate and State Rep. Rick Saccone in Canonsburg, Pennsylvania, U.S., March 13, 2018. REUTERS/Brendan McDermid

A leading Washington, D.C. polling firm warned the legislators in no uncertain terms that intense Democratic antipathy toward President Donald Trump could spur those voters to turn out in record numbers, jeopardizing safe Republican districts and potentially costing the party control of Congress.

The firm’s presentation, viewed by Reuters and not previously reported, showed a significant “intensity gap” between the two parties, with 82 percent of Democrats strongly disapproving of the job Trump is doing as president, while 56 percent of Republicans strongly approve of his performance.

Alarms over the intensity gap were sounded recently to big-ticket donors at retreats organized by billionaire Republicans Charles and David Koch in Palm Springs and by Republican National Committee (RNC) chair Ronna McDaniel in Washington.

“Complacency is our worst enemy,” McDaniel said at the Conservative Political Action Conference last month. “Democrats have the energy.”

Republicans were given fresh reason for concern on Wednesday, as Democrat Conor Lamb remained slightly ahead of Republican Rick Saccone in a too-close-to-call special congressional election in Pennsylvania. The race was in a district Trump won handily in 2016.

Interviews with more than 20 Republican lawmakers, operatives and strategists nationwide reveal a party increasingly worried about high levels of enthusiasm on the Democratic side.

Republicans are also struggling to motivate their voters to come out in the numbers needed to retain the party’s grip on the U.S. Senate and the House of Representatives.

“It’s a challenge, it is,” said Jeff Flake, a Republican U.S. senator from Arizona who is retiring this year. “We’ve got our work cut out for us.”

Issues that typically fire up conservatives when a Democrat is in the White House, including gun control, abortion, immigration and healthcare, have lost potency with Republicans in control of the White House and Congress as well as both legislative chambers in 32 U.S. states.

Many Republican operatives and lawmakers believe their best argument will be the state of the economy and the tax overhaul passed by Congress late last year. They also think the party’s fundraising power can boost Republican candidates and get-out-the vote efforts in critical contests.

But some worry tax reform is not enough to get Republican voters to cast ballots in congressional races.

“Republicans are going to struggle to turn out voters if we can’t get a lot more accomplished before November,” said Chris Wilson, a Republican pollster involved in key Senate races in Arizona, Nevada, Texas and elsewhere.

‘WE’RE IN RE-FREAKOUT’

After a brief period of optimism when the tax package passed in December, Republicans are openly fretting about their party’s image as Trump’s White House appears gripped by turmoil, with a range of policy fights on key issues, a new round of high-level departures and ongoing probes into alleged ties between Trump’s election campaign team and Russia.

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“We’re in a re-freakout right now,” said Doug Heye, a former top official at the RNC. “If the conversation is on Russia, or White House discord, or Trump’s tweets, we’re clearly not doing what we need to do.”

Republicans have watched with deepening alarm as highly motivated Democratic voters came out in force in state special elections in Kentucky and Wisconsin, and in Texas primaries last week.

It happened again in Pennsylvania on Tuesday, when energized Democratic voters flocked to the polls. Trump won the district in 2016 by nearly 20 percentage points, but many of his supporters stayed home this time.

“We should take seriously the fact that when you feel as though you are out of power and out of control of your government, you are going to respond with a higher level of engagement than you would otherwise,” said Dennis Revell, a board member of the California Republican Party.

The polling firm at the meeting in Sacramento warned that presidents who have an overall approving rating of under 50 percent — as Trump does - typically lose an average of 40 seats in midterm elections.

Democrats need to gain a net total of 2 Senate seats and 24 House seats to take control of those chambers.

‘FEEL THE HEAT NOW’

To counteract the enthusiasm gap, Republican strategists say, candidates will need to run smart and well-funded campaigns.

The polling firm urged Republican incumbents in California to focus on fundraising and to hold town halls without delay in order to draw out criticism as early as possible and energize voters.

One slide in the presentation urged Republican candidates to: “Feel the heat NOW, not in November.” Another counseled candidates to “prepare for a negative campaign” and not shy away from giving opponents “name ID, especially if that name ID is of the negative kind.”

In Washington, one Republican operative said, the party’s House incumbents were given a set of tips: Don’t take supposedly safe districts for granted. Raise money. Introduce legislation to help constituents.

“The anti-Trump Trump haters are quite energized for getting out the vote and also raising money,” Republican U.S. Representative Chris Collins told Reuters on Wednesday. “And so the message (for Republicans) is, control your own destiny. Raise money, make sure you’re out and about.”

One advantage the Republican Party holds over its Democratic counterpart is financial. At the end of January, according to a Reuters analysis of each of the parties’ three main political action committees, the RNC had a sizable money advantage over Democrats at the end of January.

Filings with the Federal Election Commission show the RNC had nearly $107 million on hand at the end of January, the last full reporting period, compared with the DNC’s $74 million.

Americans for Prosperity, a conservative group backed by the influential Koch brothers, says it will be active in Senate races and spend much of its money early in the campaign in the belief that is its best opportunity to shape the narrative of individual contests.

In the last three congressional elections, Republicans held the enthusiasm advantage, animated by their opposition to Barack Obama and Hillary Clinton and galvanized by hot-button issues such as immigration, guns, and healthcare.

Navigating those issues may be trickier now. Republicans must defend 23 House districts won by Democrat Hillary Clinton in the 2016 presidential election and dominated by more moderate, college-educated voters.

The party also needs conservatives to vote heavily in rural states such as Montana, North Dakota, and Missouri, where Republicans hope to oust five moderate Democrats.

Wilson, the pollster involved in U.S. Senate races, warned that if bipartisan deals are reached in Congress on gun control and immigration in coming months, Republican turnout could be depressed.

“It’s a complete recipe for a demoralized base,” Wilson said.

Conservative activists say some cultural issues will still pack a punch.

Penny Nance, president of Concerned Women of America, said the failure in February of a Senate bill that would have outlawed abortion after the 20th week of a pregnancy could be used against Democratic senators who opposed it, including North Dakota’s Heidi Heitkamp.

Matt Schlapp, chairman of the American Conservative Union, suggested that Trump’s ongoing attacks on the media are popular with his base of voters and could be an effective rallying cry.

But the most effective way for the party to have a unified message rests on the economy, operatives said,

“You have to show people what you are doing to improve their lives,” said Tim Phillips, Americans for Prosperity’s president. Still, he conceded it is harder to motivate voters to come out when Republicans are the party in power.

“It’s fair to say it’s easier to vote against something than for it,” he said.