The Democrats currently control 53 of 100 seats in the Senate. Nearly half of those—23—are up for re-election this year, while the Republicans are defending only 10 seats. That fact, combined with an electorate none too pleased with incumbents, made for a grim picture for the majority party at the start of this cycle.
And yet, the Democrats now have a 75 percent likelihood of controlling the next Senate, possibly by a comfortable margin.
In early September, we saw four critical races shifted to the Democratic column: Missouri, Wisconsin, Massachusetts and Virginia. Today, the Democrat is up in all four races, though three of the four remain competitive. Now, we're seeing five other races once considered safe for the Republican showing signs of equivocation: Nevada, North Dakota, Indiana, Arizona and Montana.