Many political insiders believe that the tides are turning these days in Washington, and for the first time since Jim Jeffords defection -- and perhaps even longer -- the Democrats actually have some momentum. But is it enough to win the six seats necessary to take over the Senate? CQ Weekly's Gregory L. Giroux thinks not.

The weight of historical evidence points to 2006 as a good election year for Democrats. Just not good enough.

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[N]ever — since senators were first elected by popular vote in 1914 — has a party gained as many as six seats when it had more seats up for grabs than the other party. That’s the history facing the Democrats, who will be defending 17 seats to the Republicans’ 15 next fall.

The GOP was helped in its 1994 victory by the whopping 22 seats that Democrats had to defend, compared to 13 for the GOP. But the math was against the Republicans in 1986 — Ronald Reagan’s midterm — because they had to defend 22 seats (and lost nine) while the Democrats had 12 up for grabs (losing only one). Republicans had so many seats to defend that year because they had dominated Senate races in Reagan’s ’80 landslide.

And, in a year where Democrats should be favored by history, they are saddled with a similarly difficult equation. The party’s four-seat gain in 2000 means defending a disproportionate number of seats this year.

As Giroux notes, the math is very difficult for the Democrats. Specifically, in order to retake the Senate, they would have to hold almost every seat they currently occupy -- including those in Minnesota (where Dayton is retiring), Nebraska (a heavily "red" state), Florida (a "red"-leaning state) and Vermont (where Jeffords is retiring). North Dakota, Washington and Michigan could also prove to be difficult races for the Dems.

On the other side of the ledger, the Democrats would need to win almost every competitive race and steal some less competitive ones as well. The Dems have heavily targeted Pennsylvania and Rhode Island, home to Rick Santorum and Lincoln Chafee, respectively, and Harold Ford is making a bid to succeed Bill Frist (who's retiring) in Tennessee. But the Democrats would also have to win at least three races in Montana, Arizona, Ohio, Nevada and Virginia where their prospects are notably lower. So perhaps Giroux is right -- that is unless something happens in the next 18 months to change things...