Through much of 2018 and especially in the weeks following the midterm elections, many opinion writers and other political pundits enthusiastically declared the Republican Party dead, or at least relegated to life support.

The commentary was eerily reminiscent of the post-2006 declarations that the GOP was no longer a viable political party.

Four years later, House Republicans were back in the majority.

When it comes to the GOP’s 2018 loss of the House, perhaps a little historical perspective — one based on numbers, not opinion — might be in order for Republicans, Democrats and the media.

In 2006, Democrats won the House national vote by 7.9 percent and picked up 31 seats; in 2018, the margin was slightly greater at 8.6 percent and they managed to flip at least 40 seats. Both were substantial victories that allowed Democrats to reclaim the majority and at least try to call it a mandate for what was then and is now an increasingly liberal policy agenda.

But it’s also important to remember that the House Republican wins in 1994, when they picked up 54 seats, and 2010 (63 seats) were even larger victories. So much for the GOP’s near-death experience.

For some added context, in 1994 when Democrats lost the House, their party had held control for an astonishing 40 consecutive years. It took them 12 years to regain the majority after losing in 1994 and eight years after losing in 2010. In contrast, after the 2006 elections, Republicans regained the majority in only four years and, overall, have held the House for 20 of the past 24 years.

If the past is prologue (though in politics, prognosticating is risky business), what do the numbers tell us about Republicans’ congressional chances going into 2020 and beyond?

Given the Democrats’ 235-seat majority, the GOP would need to take back 18 seats to regain the majority in 2020 — a tough but hardly impossible task.

Is this wishful thinking or a real possibility? Perhaps a little of both. For the GOP, it would mean winning virtually all current Republican-held House seats, including those they won with less than 53 percent of the vote — a number similar to the situation facing Democrats.

Despite a significant increase in turnout, the 2018 election did not deliver the structural change in the electorate that the Democrats wanted, as ideology and party ID from exit polls show. Voters changed preference, not necessarily ideology, and several key voter groups led that shift.

Start with independents. Republicans lost them by 12 points last fall; in 2016, they won the group by 6. Given that 30 percent of the electorate are independents, simply getting back to Republicans’ previous levels of support among this group would significantly affect their chances in 2020.

The same goes for female voters. In 2018, the GOP lost them by 19 points but only by 10 two years earlier. Because women make up the majority of the electorate at 52 percent, reducing the margin of loss by 9 points would put control of the House in play. Add suburban, younger, senior and Hispanic voters into the mix, and neither party can take anything for granted heading into 2020.

If Republicans can reverse enough of the changes in voter preferences seen in the 2018 election and get back to the support they garnered in 2016 or even 2012 with key groups, an opening exists.

Now for the reality check.

Admittedly, given today’s negative political environment and evolving electoral demographics, winning two-thirds of those endangered Democratic seats will be tough. I remember the months after Republicans lost the House in 2006, and I can say things didn’t look much better. Yet, four years later Nancy Pelosi was handing the gavel back to Republican John “Where are the Jobs?” Boehner.

Election Day exit polls show attitudes about the direction of the country then and now are very similar. In 2006, 41 percent said the country was headed in the right direction while 55 percent said it was on the wrong track. In 2018, it was 42 percent (right direction) to 45 percent (wrong track). Presidential job approval rating is actually slightly better for Republicans. President George W. Bush was underwater in 2006 with 43 percent approval. In 2018, President Donald Trump’s approval rating was 45 percent.

The biggest difference between the two elections is the electorate’s attitude toward the economy. In 2006, 49 percent of voters rated the economy as excellent/good while 50 percent who said it was not so good/poor. In 2018, positive attitudes toward the economy outweighed the negative, 68 percent to 31 percent.

Comparing the Winston Group’s monthly surveys from December 2006 and December 2018, Republicans should take heart. On who can better handle the economy, the GOP starts off 8 points better than it did in 2006, going from trailing Democrats by 4 to leading them by 4. On the issue of jobs, there has been a 19-point swing in the GOP’s favor from -16 to +3.

Despite the recent volatility in the markets, the economy remains a plus for both Trump and congressional Republicans. If that continues, it should create a better environment for the GOP than the fall of 2008 when the country lost about 400,000 jobs a month in the three months preceding the election.

Nonetheless, the impact of the presidential election remains as much a question mark this cycle as it did in 2008. The tenor of the Democratic primaries could be a big negative factor in 2019. So could the increasingly liberal ideology of the Democratic Party agenda and its congressional focus in the coming months.

While the Trump factor may also affect GOP prospects, the key for Hill Republicans is to move forward as they did in 2006. The ability of House and Senate Republicans to offer a positive agenda that addresses people’s kitchen table priorities, from jobs, wages and now retirement fears to health care concerns, could well decide who controls the next Congress.

David Winston is president of the Winston Group and a longtime adviser to congressional Republicans.