Battle for Senate is a Toss Up

The Upshot: “Every day, our computer churns through the latest polls and reams of historical data to calculate both parties’ chances of winning control of the Senate. Although the Democrats currently have a 51% chance, that doesn’t mean we’re predicting the Democrats to win the Senate — the probability is essentially the same as a coin flip.”

“The Republicans’ chances have been declining in recent weeks, falling from a recent high of 54%. This is mostly due to some unfavorable polls in Arkansas and Iowa.”

The model behind these projections is called LEO.