As a new Congress convenes, it has become an unquestioned truth among Republicans that their party has as much of a mandate as President Barack Obama because voters returned them to power in the House.

The mantra has been intoned by John Boehner, Paul Ryan, Mitch McConnell, Newt Gingrich, Grover Norquist and many other party eminences, and there is a certain logic to saying that the voters, by giving Republicans the House, were asking for divided government.

But the claim to represent the voters' will doesn't add up.

The final results from the November election were completed Friday, and they show that Democratic candidates for the House outpolled Republicans nationwide by nearly 1.4 million votes and more than a full percentage point – a greater margin than the preliminary figures showed in November. And that's just the beginning of it: A new analysis finds that even if Democratic congressional candidates won the popular vote by 7 percentage points nationwide, they still would not have gained control of the House.

The analysis, by Ian Millhiser at the liberal Center for American Progress using data compiled by the nonpartisan Cook Political Report, finds that even if Democrats were to win the popular vote by a whopping 9 percentage points – a political advantage that can't possibly be maintained year after year – they would have a tenuous eight-seat majority.

In a very real sense, the Republican House majority is impervious to the will of the electorate. Thanks in part to deft redistricting based on the 2010 census, House Republicans may be protected from the vicissitudes of the voters for the next decade. For the Democrats, this is an ominous development: The House Republican majority is durable, and it isn't necessarily sensitive to political pressure and public opinion.

According to the Jan. 4 final tally by Cook's David Wasserman after all states certified their votes, Democratic House candidates won 59,645,387 votes in November to the Republicans' 58,283,036, a difference of 1,362,351. On a percentage basis, Democrats won, 49.15 percent to 48.03 percent.

This in itself is an extraordinary result: Only three or four other times in the last century has a party lost the popular vote but won control of the House. But computer-aided gerrymandering is helping to make such undemocratic results the norm – to the decided advantage of Republicans, who controlled state governments in 21 states after the 2010 census, compared with 11 for Democrats.

To be sure, Democrats tend to be just as flagrant as Republicans when they have the chance to gerrymander. But the Republican advantage isn't entirely because of redistricting; Democrats have lopsided majorities in urban clusters, so the overall popular vote overstates their competitiveness in other districts. An analysis by FairVote found that nonpartisan redistricting would only partially close the gap, which also comes from the disappearance of ticket-splitting voters who elected centrist Democrats.

But the 2012 House results show the redrawing of districts to optimize Republican representation clearly had an impact. Consider three states won by Obama in 2012 where Republicans dominated the redistricting: In Pennsylvania, Democrats won just five of 18 House seats; in Virginia, Democrats won three of 11; and in Ohio, Democrats won four of 16.

Using Wasserman's tally, Millhiser ranked districts by the Republican margin of victory and calculated that for Democrats to have won the 218 seats needed for a House majority they would have had to add another 6.13 percentage points to their popular vote victory margin of 1.12 points.

To put the Republican advantage in perspective, Democrats could only win the House if they do significantly better than Republicans did in their landslide year of 2010 (when they had a 6.6-point advantage). That's not impossible – Democrats did it in 2006 and 2008 – but it's difficult. Republicans don't have a permanent House majority, but they will go into the next several elections with an automatic head start. For many, the biggest threat comes not from Democrats but from conservative primary challengers.

In theory, the Supreme Court could decide that this rigged system denies Americans fair and effective representation. But this won't happen anytime soon. For now, Democrats need to recognize that the Republican House majority will respond only sluggishly to the usual levers of democracy.

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