Washington (CNN) The House playing field just keeps tilting toward Democrats as the November midterm election creeps ever closer.

With just 99 days left in the 2018 cycle, Democrats appear poised to retake the House majority they lost in the 2010 election, according to a new analysis by CNN's own Terence Burlij.

The math goes like this: Democrats need to net 23 Republican-controlled seats to win the majority. At the moment, CNN rates 11 Republican-held seats as "leaning Democratic" or worse for the GOP. Let's assume those 11 seats go for Democrats.

Now, we are down to only 12 additional pickups for Democrats to win the majority. Take a gander at the "toss-up" ratings in the chart above. Of the 27 seats currently rated as "toss-ups" by CNN, Republicans control 25 of them. If Democrats win just under half -- 12 -- of those GOP seats, they are back in the majority. (Traditionally, one party tends to win the vast majority of the "toss-up" races because House contests -- particularly very close ones -- tend to be heavily affected by the national mood. And the national mood typically favors one side at the end of an election.)

The other math problem for Republicans -- aside from the large amount of vulnerability they carry in seats they currently hold -- is how few opportunities they have of picking off Democratic seats. CNN rates only 13 Democratic seats as competitive at all -- with just two "toss-ups" and four that lean in Democrats' favor. There are zero Democratic-held seats where Republicans are currently favored.

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