President Obama’s decision to highlight his support for greater action to tackle climate change during this autumn’s election campaign looks to have been vindicated, after a new poll revealed a clear majority of undecided voters want the US government to take more ambitious steps to reduce greenhouse gas emissions.

The poll from Yale and George Mason Universities surveyed 1,061 US adults and found that undecided voters’ attitude towards climate change and energy policy was much closer to that of declared Obama voters than Romney voters. Significantly, 55 per cent of undecided respondents also said that global warming was an important issue that was likely to influence their eventual vote.

The survey found that 80 per cent of undecided voters believe global warming is happening, while only three per cent stated that it is not happening. This is largely in line with the 86 per cent of Obama voters who believe global warming is happening, and in stark contrast to the 45 per cent of Romney voters who agree global warming is occurring.

A two-thirds majority of undecided voters also accept that if global warming is happening it is mostly caused by human activity, again in contrast to likely Romney voters.

This acceptance of the scientific consensus translates into a strong desire for more action from Washington to address climate risks.

“Undecideds as well as likely Obama voters say that President Obama (64 per cent and 61 per cent respectively) and Congress (72 per cent and 78 per cent) should be ‘doing more’ about global warming,” the report states. “By contrast, fewer than half of likely Romney voters think the President or Congress should be doing more (35 per cent and 35 per cent respectively) and, in fact, are more inclined to say they should be doing less to address global warming (47 per cent and 44 per cent).”

The margin of error for undecided was 11 per cent, as a result of the relatively small sample size. But the poll will still represent a further boost to Obama, particularly given 55 per cent of undecided said that global warming policy represented one of several important issues that would influence their vote and a further six per cent said it would be the single most important issue.

Moreover, the poll revealed strong support for Obama’s pro-renewables energy policy, confirming that 85 per cent of likely Obama voters and 83 per cent of undecided voters agree “that in the future US should use more renewable energy sources”.

Interestingly, 73 per cent of likely Romney voters also agree with the statement, suggesting Republican opposition to renewable energy support programmes may not be as popular with their base as has been widely believed.

The poll was released yesterday in the midst of a series of manoeuvres on Capitol Hill designed to push environmental issues further up the political agenda in the run-up to the presidential election in November.

The Senate passed its version of a bill that would stop US airlines from complying with the EU emissions trading scheme over the weekend, potentially paving the way for a difficult decision for the President that could force him into a trade war with Europe over aviation emissions levies.

Meanwhile, the Republicans pushed a Stop the War on Coal bill through the House of Representatives in their latest attempt to overrule the US Environmental Protection Agency’s (EPA) regulations on coal plant emissions, and the Senate passed new energy efficiency legislation despite having to water down proposed new standards for a range of products in order to gain sufficient Republican support.