Here’s something I bet you haven’t heard anywhere else: The Colorado House and Senate each could flip next year.

OK, maybe you’ve heard half that. The Republicans hold just a one-seat edge in the 35-member Senate, which will see 17 seats on the ballot next year.

But the House? Democrats enjoy a nine-seat majority in a chamber that, at best, has five competitive districts out of 65. Republicans would have to run the table or notch some surprises.

So what does Ballotpedia know about 2018 that the rest of us who follow the Colorado statehouse don’t? Math.

Democrats hold seven seats in the House that they won by less than 10 percent last year. Republicans had two. And that equals five, which is how many the GOP would have to win to take the majority.

The analysts also looked at the number of overall elected officials statewide, which tilts heavily to the right in down-ballot statewide offices and even farther to the right in offices elected outside the Democrat- and population-heavy Front Range.

But there are other factors, including a general national trend of voters preferring that Republicans run state government. During Barack Obama’s presidency, Democrats lost more than 1,000 legislative seats across the country.

With Donald Trump in the White House, it’s possible if not likely that Democrats will be energized next year, as Republicans were in 2010 and 2018.

Ballotpedia didn’t factor in historical voter turnout in midterms by the parties for this report, but analyst Rob Oldham said that his been a problem for Colorado Democrats in recent elections.

The Denver-based polling first of Magellan Strategies looked at that in an analysis last January:

“Midterm elections are crucial here, because that’s when elections for our statewide offices are held,” Magellan reported. “In the past two midterm elections, Republicans have been able to win seven out of the 10 elections for statewide office, the only losses being the elusive governor’s office (twice) and Sen. Michael Bennet’s election in 2010. The seven wins include Sen. Cory Gardner in 2014, and then a 6-0 sweep in the contests for secretary of state, state treasurer and attorney general. Republicans, going back at least half a century, have historically dominated those three offices.

“… Still, it’s not as though Republican candidates are winning these elections by wide margins. The average Republican share of the vote in those seven wins from 2010 and 2014 is only 50.5 percent, and that’s including the re-election of Attorney General John Suthers in 2010, which at 56.3 percent is something of an outlier.”

Democrats built a big House majority last year by picking up three seats last November, when Barbara McLachlin beat J. Paul Brown in southwest Colorado, Tony Exum won back his seat in Colorado Springs from Kit Roupe and Dafna Michaelson Jenet unseated JoAnn Windholz in Commerce City.

Michaelson Jenet and Exum both won by 8 points last year, and in the state’s most competitive House district, McLachlan took it with half a percentage point – just 325 votes.

In the 2016 election, the one-seat majority in the Senate held.

Republican Sen. Laura Woods lost to Rachel Zenzinger in District 19 in Arvada, but former Rep. Kevin Priola of Severance took the District 25 seat previously occupied by Democrat Mary Hodge of Brighton.

There were nine open seats in the state Senate last year, but three of the newcomers (two Democrats and one Republican) ran unchallenged in the general election.

If the minority party wins the battle in both chambers, that would put Republicans in charge of the House and Democrats over the Senate. That means the same partisans battles and bill-killing would continue unabated.

Ballotpedia is predicting competition in 15 chambers. Besides the Colorado House and Senate: