Beyond the tipping point

Tier Three: also competitive
As more Republican-held seats move into Tier Two's danger zone, Tier Three shrinks. If Democrats are picking up third-tier seats on Election Night, they'll likely be headed toward a net gain of 30 or more.

Republicans are counting on their vaunted get-out-the-vote machine to help them overcome a hostile environment. Yet, as one Democratic strategist observed, "All the technology in the world can't do a thing about a pissed-off voter." A strong and sophisticated turnout operation works best when a party's base is at least as motivated as the other side's.

National polls have consistently shown a rather sizable enthusiasm gap, with Republicans much less eager than Democrats to cast ballots. In a Pew Research Poll taken September 21 to October 4, more than half, 51 percent, of Democrats but only 33 percent of Republicans said they were more enthusiastic than usual about voting. Yet one Republican strategist argues that polling in the key battleground districts has not found that the GOP base is turned off. Polling consistently indicates that independents -- who admittedly are less likely to vote in midterm elections than either party's diehards -- want Democrats to take control of Congress.

It's not that Americans view the Democratic Party as more appealing than the GOP. The latest NBC/Wall Street Journal poll showed Democrats with a 39 percent approval rating, just 4 points higher than Republicans' rating. The same poll, however, put the Republican Party disapproval rate at 48 percent, 13 points higher than the Democratic Party's.

If Democrats take control of the House, as seems very likely, they'll have voters' hostility to the GOP -- not their own popularity -- to thank. The political environment has not been this bad for any party since 1994. The dour public mood has created a playing field so lopsided that Republicans have more than seven times as many vulnerable seats to defend as Democrats have. Predicting a Democratic gain of 20 seats -- an outcome that looked impossible just a few months ago -- now seems cautious.

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