(CNN) Senate Majority Leader Mitch McConnell said this week that the race for control of the Senate is so close it is like a "knife fight in an alley." New polls released on Wednesday back him up, but also show that Republicans are still favored to maintain their control.

Fox News found the races in Arizona, Indiana, Missouri, North Dakota and Tennessee are all within 4 percentage points. Republicans are up in Indiana, North Dakota and Tennessee. Democrats are up in Arizona and Missouri.

The averages in some of these races -- such as Arizona (a little more friendly to Republicans) and Tennessee (a little more friendly to Democrats) -- differ slightly with Fox News. They mostly tell the same story, though: Democrats have an uphill battle for control of the Senate.

Democrats would need to win at least four of these five states to have a realistic shot of gaining that control. (They need a net pickup of two seats overall.) The closeness of the races means that's certainly possible. But while the outcomes are correlated, it's a little much to expect Democrats to sweep the board given the current polling.

The good news for Democrats is that the strongly pro-Democratic national environment gives them a better shot than you might think. The bad news is that the states the Senate battle is being fought in are not friendly to Democrats.

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