With candidates poised to spend billions of dollars to win over voters ahead of next year’s US presidential election, the politician making the biggest mark so far is one who has no intention of being on the ballot.*
Elizabeth Warren, the Massachusetts Democrat, is using her political rock-star status and attacks on corporate greed and Wall Street excess to push her party and its presumed presidential nominee, Hillary Clinton, to the left.
In the ascendant, Ms Warren this week clashed with President Barack Obama over a bill that would grant him authority to conclude a sweeping Pacific Rim trade accord, one of the signature items on his economic agenda.
Facing a Warren-led revolt against legislation she insists will benefit big business at the expense of US workers, Mr Obama was forced to turn the screws on Senate Democrats to forge a compromise.
In some respects, Mrs Clinton was likely to tack left. In spite of her family’s cosy ties with Wall Street, she has long spoken out on inequality and the need to give a leg up to still-struggling middle class families.
While she has declined to spell out a clear position yet on trade, her rhetoric on the campaign trail has been decidedly Warren-esque, telling voters that the “deck is stacked” in favour of the rich and deriding the excesses of CEO pay.
But it is not clear the electorate is entirely ready for a progressive moment.
In an America where a majority of the population now backs same-sex marriage, recreational marijuana use is legal in four states and leading Republicans as well as Democrats have pledged to address the rising gap between the rich and the poor, polls show US attitudes have indeed become more liberal in certain areas.
Some elements of a so-called “populist” economic agenda, such as hiking the federal minimum wage and requiring businesses to provide staff with paid sick leave, are already supported by a majority of Americans.
But on the central question of whether the government should play a much more interventionist role in tackling inequality, wage stagnation and declining social mobility, as progressives such as Ms Warren advocate, the picture is far less certain.
That is because while most Americans say they are dissatisfied with the way the country’s income and wealth is distributed, they do not agree on the reasons why there is such a gap and whether the government should be responsible for addressing it.
For example, as many are likely to blame rising inequality on Democrats and liberal policies, such as expanding entitlement programmes, as they are on Republicans and traditionally “conservative” policies, such as lowering taxes.
It is a similarly nuanced story on trade. In a poll released earlier this month, 37 per cent of Americans said free trade with other countries had helped the US, compared with 31 per cent who said free trade had hurt. That may not sound like a big difference, but it marked the first time in 15 years that more Americans were positive than negative on the subject.
Centrist Democratic strategists have long warned of the risks of a sharp leftward tilt into economic populism. The party was shellacked in midterm elections in November, losing its majority in the Senate for the first time in eight years and seeing Republicans increase their grip on the House of Representatives after failing to convince voters they had a clear agenda for boosting growth.
Democrats have only to look across the Atlantic to Britain where Ed Miliband misjudged the public mood and led his Labour party to a crushing election defeat last week to see the perils of failing to get the message right on the economy.
Ms Warren has so far been very canny in harnessing her star power to shift the debate to the left. Whether she can keep it there is another story.
*This story has been amended to clarify that billions of dollars, rather than hundreds of billions, would be spent as part of the 2016 election campaign.
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