America: The candidates were all smiles at the Democratic National Committee headquarters in Washington this week when supporters met for breakfast to cheer on the party's challengers for marginal congressional seats in Pennsylvania.
If the Democrats are to win the 15 seats needed to regain the House of Representatives, they must do well in Pennsylvania and polls give the four candidates on display this week an excellent chance of success.
They were an impressive group: Lois Murphy, a liberal lawyer who came within two points of winning a seat in 2004; Chris Carney, a political scientist and former Pentagon adviser who serves in the navy reserve; Joe Sestak, a retired admiral who served as a national security adviser to President Bill Clinton; and Patrick Murphy, a young captain recently returned from duty in Iraq.
With Democrats leading Republicans in the polls by 11 per cent and President George Bush's approval rating stuck around 40 per cent, all the indicators point to a Democratic victory in six weeks. Yet despite encouraging words from veteran congressman John Murtha, there was anxiety at this week's breakfast, as if the Democrats can't believe they won't allow the prize to slip from their grasp again.
The Democrats' problem is not solely one of self-esteem; they are acutely aware that Republicans have a $30 million advantage in campaign funding and a more unified, professional campaign team. While the Democrats this week patched up a long-running dispute over resources between Democratic national committee chairman Howard Dean and Congressional campaign committee chairman Rahm Emanuel, Republicans were showing just how effective their voter mobilisation strategy remains.
Rhode Island senator Lincoln Chafee, the only Republican who voted against authorising the war in Iraq, faced down a formidable primary challenge from Stephen Laffey, a conservative populist. Mr Chafee owed his victory in large part to a $400,000 campaign by the Republican National Committee, which reckoned that Mr Laffey was too conservative to hold the seat in one of the country's most liberal states.
Using a sophisticated database called the Voter Vault, which tracks the specific concerns of individual voters, dozens of volunteers brought into the state for the last days of the campaign "microtargeted" swing voters with personalised telephone campaigning.
Democratic strategists acknowledge that the Republican voter turn-out strategy is more impressive than their own but are confident that Democratic supporters will be more motivated to vote in November, not least to protest against Mr Bush's more unpopular policies, such as the war in Iraq.
Mr Bush is undoubtedly a liability for Republicans but there are signs that his decision to focus on national security during the past few weeks is beginning to pay dividends. An ABC News poll this week gave Republicans a lead of 7 per cent when respondents were asked which party they trusted to handle terrorism, a 14 per cent improvement from last month.
Republican hopes of portraying Democrats as weak on national security have received a setback with the decision of four leading Republican senators, including presidential hopeful John McCain, to oppose the president's proposal to reinterpret Geneva convention rules governing the interrogation of terrorist suspects.
Democrats have, for the most part, stayed out of the debate so far, leaving Mr McCain and other Republicans, including former secretary of state Colin Powell, to argue that reinterpreting the rules could leave US soldiers more vulnerable to torture in the future. With no good news from Iraq and growing popular discontent about illegal immigration and rising fuel prices, however, Republicans believe that national security remains their strongest card during the campaign.
Democrats fear they have yet to face the full force of the Republican electoral effort, which is likely to include saturation campaigns of negative TV advertising in the most closely contested constituencies. Some Democratic strategists are already looking beyond November and consoling themselves with the prospect of a weakened Republican Congress and a lame-duck president struggling on for two years until, they hope, Democrats sweep back into control of the White House, the Senate and the House of Representatives.