The latest from Larry Sabato:

Although the GOP would prefer to avoid the former scenario, almost all indications now point towards voters coming out in slightly higher-than-average midterm election percentages, at least in part to lash out at the party in power. The most reliable surveys show Democrats disproportionately engrossed in the elections, all the more reason a truly Herculean late identification and mobilization effort under the direction of Karl Rove, Ken Mehlman, and other wizardly GOP strategists would be needed to minimize Democrats' turnout edge. Of course, we don't want to make the mistake that some are committing by bringing down the curtain on the election too soon. Elections cannot be hurried; they must fully unwind on their own schedule, which this year ends November 7th.

For the GOP, the Senate has always trailed behind the House in vulnerability to takeover. But in the last month, as Democrats have more likely than not wrested the House onto their side in this year's grand tug of war, the Senate has become more of a 50-50 proposition. The Crystal Ball will always have one eye firmly fixed on the House, where Democrats are poised to win 20 to 25 seats if not more. But this week, we turn our attention to the upper chamber, where five fundamentally close races will likely determine which party ends up on the short end of 51-49 (or in Democrats' case, the short end of 50-50, given Vice President Cheney's tie-breaking ability).

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Readers will wonder why noted races in Montana, Ohio, and Pennsylvania are not in this group. In our view, without a small miracle, GOP Sens. Conrad Burns, Mike DeWine, and Rick Santorum are all now headed into early retirement. Likewise, Republican takeover opportunities in Nebraska, Washington, and elsewhere have faded, and Maryland's open seat remains only a glimmering hope for the GOP as Maryland's strong Democratic lean manifests itself closer to Election Day. Democrats would have to win four out of the "Fundamental Five" to get to 51 seats, but with only one of the five currently leaning ever-so-slightly to the GOP, it's not as if the chances of such a scenario could even be described as on a noticeable incline, let alone uphill.

His full analysis here.