ELECTION fever grips the American Left. A mood of scrappy, let-us-at-’em impatience unites such gatherings as Netroots Nation, an annual shindig which this year drew thousands of activists, organisers, bloggers and candidates to Detroit from July 17th-19th. Unfortunately for the broader Democratic Party, the election that inspires the grassroots is the 2016 presidential race. The mid-term congressional elections, which will happen much sooner (in November this year), provoke a more muted response, even though there is a good chance that Republicans will seize the Senate and cripple the rest of Barack Obama’s presidency. The kind of people who attend Netroots Nation are passionately and uncompromisingly left wing. Their champion is Senator Elizabeth Warren of Massachusetts, a former professor who crusades against “big banks”, “powerful corporations” and their enablers on the Right. “The game is rigged,” thundered Ms Warren, whose demands include more generous Social Security benefits (pensions) for the old (paid for with steep tax hikes), cheaper student loans, a higher minimum wage and other forms of redistribution. Not for her the business-friendly centrism of the Clinton clan. Hillary Clinton did not attend Netroots Nation, instead giving a TV interview in which she suggested that a bit of economic growth might make it easier to curb inequality.

Sweet dreams are made of this

Ms Warren’s warm-up act was Gary Peters, a local congressman who, unlike Ms Warren, is running for election this year. Mr Peters, a moderate ex-banker, is trying to win a Senate seat that Democrats desperately need to win but might not. He could use some grassroots support, but the crowd barely noticed him. They were too happy chanting “Run Liz, Run!” or waving “Elizabeth Warren for President” boater-style hats (“they’re fun, they’re old-timey,” said a hipster handing them out). Ms Warren says she is not running for the White House. No matter. Some 100 days from an election that could condemn Mr Obama to near-impotence, some progressives prefer to daydream about President Warren, “who won’t stand for all the Wall Street bullshit”, to quote a new (endearingly terrible) folk song by her supporters.

The Democrats’ footsoldiers can ill afford to daydream in 2014. Even as digital technology transforms elections, recent research shows that flesh-and-blood volunteers tend to trump paid advertising. Candidates need supporters to sway their friends and neighbours. This “ground war” is most crucial, for both sides, in the half-dozen swing states where Senate races could go either way. The trouble is, these states are quite conservative. So the Democrats running for office there often have views on guns, coal or fracking that appal progressives, who are therefore reluctant to knock on doors for them.

Like the Republicans with their Tea Party zealots, the Left must choose between purity and pragmatism. MoveOn, a lefty campaign behemoth which claims 8m members, has endorsed only nine Senate candidates so far in this election cycle, conspicuously excluding centrists in tight races in Georgia, Kentucky and Louisiana. The group will “sit out” some races; its members have drawn a “bright line” against endorsing senators who voted against increased background checks for gun-owners, for instance. In 2014 that rules out Mark Begich in Alaska and Mark Pryor in Arkansas.

Another group, the Progressive Change Campaign Committee (PCCC), whose members raised over $2.7m for 2012 candidates, calls itself “the Elizabeth Warren wing of the Democratic Party”. Its leaders can sound Tea Party-ish, declaring that “ideology” matters as much as finding candidates who can win. The PCCC has invested in such hopeless causes as the Senate race in South Dakota to demonstrate the power of “anti-corporate” messages delivered by the Democratic candidate there. Several leftish groups think the mid-terms are a chance to show that economic populism is the best way to woo unhappy voters, nationwide.

Yet Tea Party parallels are imperfect. Flinty conservatives often scoff that moderate Republicans are no better than Democrats. Progressives are different: many think that Republicans are wicked. That pushes their leaders, at least, towards pragmatism. “We may have to compromise on some things [to beat the Republicans],” says a boss at Democracy For America (DFA), a group founded by Howard Dean, a former Vermont governor and presidential hopeful who claimed to represent “the Democratic wing of the Democratic Party”. Take Alaska’s embattled senator. To DFA, Mr Begich has been “terrible” on oil and gas and “not good” on guns. But he is “fantastic” on inequality. In Louisiana local DFA members are holding their noses and helping a pro-oil Democrat, Senator Mary Landrieu. Ultimately, DFA vows to be “all over” any race that might decide the fate of the Senate. Should Democrats lose in 2014, blame candidates “who didn’t run on expanding Social Security or [raising] the minimum wage,” insists Charles Chamberlain, DFA’s executive director.

Both DFA and the PCCC plan to use digital wizardry to help members place campaign calls to districts across the country: a nifty trick in places where members despise their own party’s local candidates. MoveOn tells activists that saving the Senate is the “most important priority” of 2014, reminding them that Mr Obama’s ability to nominate judges is in the balance. Over on the centre-ground, Ready for Hillary, a group working to rally a volunteer army for Mrs Clinton’s use (should she choose to run in 2016), will “amplify” any 2014 endorsements made by their heroine, instantly urging supporters to lend a hand to that campaign.

On current showing, many will ignore such calls to arms in 2014. Despair with Mr Obama and this Congress may be part of the explanation. Progressive footsoldiers are waiting for the scrap that really interests them: a fight to drag the Democratic Party leftwards to victory in 2016. Republicans, who have plenty of problems of their own, cannot believe their luck.