Is Kamala Harris’s scramble for Republican endorsements about to blow up in her face?

Six weeks before election day, most voters have made up their mind about who they will support on November 5.

Postal ballots have been sent out, and early voting in some states has begun. For some, the campaign is already over.

With the result predicted to be so close, Kamala Harris is running a guerilla campaign against Trump, by picking off high-profile Republicans who can be convinced to publicly endorse her.

Ms Harris’s team has launched “Republicans for Harris”, an official arm of her campaign that pumps out endorsements from her traditional enemies.

The biggest endorsement so far is from Dick Cheney, the former Republican vice president, and a slew of former officials, politicians and advisers have joined him in praising the Democratic ticket.

At the Democratic National Convention last month, a parade of former Republican officials, including some Trump administration staff, warned voters not to put him back in the White House for a second term.

On Friday, Nikki Haley’s campaign manager in Iowa became the latest strategist to break ranks and join her team.

However, the strategy has raised concerns from some observers, who worry Ms Harris runs the risk of alienating her liberal base.

The Republicans for Harris strategy has emerged during an incredibly tight presidential race, in which a few switchers could make a major difference to the result.

Within each of the seven battlegrounds, the margin of votes is very small. No candidate has a lead of more than four points in any of them, and most polls put the predicted result within the statistical margin of error.

That means voters who switch sides have enormous value to both campaigns. A switcher is effectively worth double an undecided voter, because their move both deducts a vote from one campaign and awards it to the other.

There are also more potential switchers than undecided voters.

14pc may still change their vote

The Telegraph’s latest swing state poll found an average of 14 per cent of voters across the swing states say they may change their choice, compared with seven per cent who have not decided on a candidate.

The data shows Ms Harris has an advantage in the political affiliation of the switchers. In the majority of swing states, more Trump voters say they are open to switching than Harris voters – suggesting Trump’s support is slightly “softer”.

However, Ms Harris is also vulnerable to a collapse in support from the Left.

Mr Cheney, who is primarily associated with the Iraq War, has an approval rating with the American public of just 33 per cent, according to data from YouGov.

Unsurprisingly, he is especially unpopular with Democrats. Former Trump officials are similarly despised by liberal voters, who could be dissuaded by their endorsement of Ms Harris.

Philip van Scheltinga, director of research at Redfield & Wilton, who polled the swing states for The Telegraph, said: “It is absolutely baffling that the Harris campaign has come out and said they are “proud” of Dick Cheney’s endorsement.

“He was a deeply unpopular Vice President, and he has done nothing since his vice presidency to rehabilitate his standing among the public, nor have his policies been vindicated in any sense.

“If public opinion had moved back in support of the Iraq War in that time, then maybe this decision by the Harris campaign would have made some sense, but it hasn’t.

“The Harris campaign has taken the extent of the feeling of the anti-Trump vote for granted.”

Riding out the storm of Middle East conflict

The polls show that Ms Harris has won back the support of some liberals who opposed Joe Biden, mostly because of his support for Israel during the conflict in Gaza.

But there are concerns in her campaign that some younger voters – especially those in swing states – could stay at home on November 5.

Young women are much more likely to support Ms Harris than Mr Biden, but may also be concerned about endorsements from Republicans who served Trump or previous GOP administrations.

Ms Harris’s campaign has done well to avoid any major negative stories since she took over from Mr Biden in July, and has pursued a “Ming vase” strategy focussed more on preventing losses than making audacious gains.

Attracting prominent Republicans, many of whom have toxic reputations with the voters she most needs, is a risky strategy.