Four weeks out from the midterms, the Senate map has gotten wider and the margins have gotten thinner.

Fox News power rankings now count eight Senate races as genuine battlegrounds. The Washington Examiner moved three of them toward the Democrats this week.

Here is the arithmetic. Republicans hold the Senate 53 to 47. Democrats need a net gain of four seats to take it back.

The generic ballot looks bad on its face. The RealClearPolitics average has Democrats up 51.2 to 42.7, a margin of 8.5 points.

But the generic ballot does not elect anybody. Seats do. And the seat-by-seat numbers tell a different story than the national one.

North Carolina is the worst of them for Republicans. Roy Cooper leads former RNC chairman Michael Whatley by nine.

Texas is the other real problem. Democrat James Talarico is running about three points ahead of Attorney General Ken Paxton in a state Republicans should never be defending.

After those two, the picture changes completely.

Maine is a tie in everything but name. Democrat Troy Jackson sits at 47.6 against Senator Susan Collins at 47.5. That is one tenth of one point.

Alaska is close to the same. Mary Peltola leads Senator Dan Sullivan 48.8 to 47.0.

In Ohio, former Senator Sherrod Brown leads Senator Jon Husted 47 to 44, and that lead shrank by a point over the past week. Michigan has Abdul El-Sayed up 3.5 on Mike Rogers. In Iowa, Josh Turek is ahead of Representative Ashley Hinson by less than a single point.

Read that list again and notice what it actually says. Outside North Carolina and Texas, every one of those Democratic leads sits inside the margin of error.

A one-tenth-point lead in Maine is not a lead. It is a coin that has not landed.

The House is tighter still. Republicans are defending a 218 to 214 majority, which means a handful of districts decides the chamber.

Two things cut against the blue wave talk. The first is money, and Republicans have more of it going into the final stretch, which matters most in exactly these close races where a few points of advertising moves the number.

The second is that forecasters have been here before. The Daily Wire noted that prognosticators are calling a wave while the underlying margins stay within the noise.

Senator Chuck Schumer has said Democrats hold the edge despite the polling and money gaps. Republicans are betting that the gap between a national mood and seven individual races is where the majority survives.

Thirty days to find out.