• Ukrainian officials are likely watching U.S. polls with more than a touch of nervousness this week, as the vote remains too close to call.
• After almost three years of fighting, there's no doubt that funding fatigue is setting in among Kyiv's biggest military backers, particularly the U.S.
• Analysts say that funding for Ukraine could decline, no matter who between Republican Donald Trump and Democrat Kamala Harris enters the White House.

Tensions are likely running high in Kyiv ahead of Tuesday's presidential election in the U.S. — a vote that could make or break ongoing aid for Ukraine.

The latest poll from NBC News showed a "deadlocked race" between Republican nominee and former U.S. President Donald Trump and the Democrats' candidate, current Vice President Kamala Harris.

For Kyiv, the big issue is how much support and financial backing it will continue to receive after White House leader Joe Biden, who has been in term throughout Russia's war in Ukraine, leaves office.

Follow: Election 2024 live updates: Trump and Harris await Presidential election results

After almost three years of fighting, there's no doubt that funding fatigue is setting in among Kyiv's biggest military supporters, particularly the U.S., despite ongoing public shows of support for Ukraine from the White House and NATO.

It's widely agreed that a Trump administration and hard-line Republicans would be far more hostile toward granting Ukraine more military aid, significantly inhibiting its ability to continue to fight back against Russia. However, it's also likely that even a Kyiv-friendly administration under Kamala Harris, who has pledged to continue supporting the war-torn nation, could struggle to convince U.S. lawmakers to give far more financial backing to Ukraine.

Officials in Kyiv say the election is being watched closely, amid concerns that future aid could be cut.

"Of course, we understand that this is one of the possible scenarios which would be heavily unfavorable for Ukraine," senior Ukrainian official Yuriy Sak told CNBC last week.

"But on our part, we will do everything to continue to convince our partners in the U.S. to maintain the funding and the support at the same level, because the alternative is bad for all parties involved, including the United States of America," he added.

"We, of course, are watching very closely what is happening. We have our opinion about the different candidates, but ... we hope and count that regardless of who is the next president, the United States of America will continue to support Ukraine until our victory and until we re-establish just peace."

Ukraine relies on its international partners for the military, humanitarian and financial needed to both keep the country functioning economically, and to remain militarily capable of fighting back against Russian forces entrenched in southern Ukraine, and those slowly advancing in the Donbas region in the east of the country.

The Kiel Institute of the World Economy, seen as one of the most reliable trackers of external aid for Ukraine, calculates that the U.S. has spent nearly $108 billion on military, humanitarian and financial aid since the start of the war in Feb. 2022 to Aug. 31 this year, while EU member states and institutions (such as the European Investment Bank and European Commission) have spent a collective 161.11 billion euros ($175.47 billion on such aid.)

The likelihood of funding drying up

U.S. largesse toward Ukraine has become an increasingly tough sell to U.S. lawmakers, with months of delays and objections from hard-line Republicans over a $61-billion aid package that was eventually passed in spring.

A crucial factor for Ukraine is whether the Democrats of Republicans dominate Congress after the election, a deciding factor in how much power the future president wields, and to what extent he or she is able to support — or thwart — Ukraine financially.

Donald Trump has heavily suggested that he would pull the plug on military aid for Kyiv, after claiming that he would stop the war within 24 hours of being elected, without providing further details of how he would do so. Analysts say it's likely that Trump sees a block on funding as a way to forcibly stop the war.

His running mate J.D. Vance is explicitly opposed to further aid for Ukraine, arguing that the U.S. should encourage Kyiv to strike a peace deal with Russia and should be prepared to cede land to Moscow.

Trump pulling the plug on Ukraine funding immediately would be an extreme scenario, according to economists at Berenberg Bank, but is a distinct possibility from a politician known for his unpredictability.

"Although Europe is the top donor to Ukraine, U.S. military assistance is vital for Kyiv," Berenberg Bank said in emailed comments last month. "Unless Europe steps into the breach fast and issues, say, €50 billion [$54.1 billion] of bonds so it can buy in the U.S. the weapons and ammunition that Ukraine needs but Europe cannot produce, Putin could win the war of attrition, forcing Ukraine into submission."

While an election win for Harris would be a relief for Kyiv, given that she has vehemently pledged her administration would support Ukraine "for as long as it takes," neither she nor Washington has ever clearly defined the exact meaning of her statement, what a Ukrainian victory looks like, or whether there is a limit to U.S. aid.

In the week before the presidential election, Western officials were reported as saying that a Harris administration would likely struggle to push significant aid for Ukraine through Congress.

CNBC has reached out to the Harris and Trump campaign teams.

Making Russia pay?

Leaders of the Group of Seven (G7) group of industrialized countries have looked to "Trump-proof" near-term aid to Ukraine ahead of the Nov.5 election, agreeing in late October a $50 billion loan to Ukraine that will be backed by frozen Russian assets.

The G7 said it would start disbursing the funds before the end of the year, essentially before any new U.S. administration can row back on the agreement.

If the U.S. pulls back on funding for Ukraine in 2025, however, Europe will be on the hook to support Kyiv going forward, making the thorny issue of continuing to use the proceeds of a deep pool of frozen Russian central bank assets — the vast majority of which are held in Europe — a pressing point.

"Now $50 billion [agreed by the G7] sounds like a lot of cash but it only amounts to 3-4 months of Ukraine's funding needs," Timothy Ash, emerging markets strategist at BlueBay Asset Management, said in emailed comments last month.

He is among those pressing for an estimated $330 billion immobilized Russian assets to be seized and allocated to Ukraine to help it continue to fight back against Russia, and he has noted the pushback from some EU nations who fear Russia will retaliate against such a move. Some nations have more to fear than others; currently, around $191 billion of all immobilized Russia assets are held in the Belgian central securities depository, Euroclear.

Ash said he would urge any future Trump administration to pressure the EU "to release the full $330 billion in assets to Ukraine."

"Ukraine could then fund its own defence and recovery," he said, flagging the country could perhaps even commit to spending a large proportion of the funds to buy defense equipment in the U.S.

"A sum of $150 billion spent in the U.S. over ten years say would be the biggest foreign defence purchase in the U.S.' history. It would save the U.S. taxpayer writing cheques for Ukraine, secure thousands of defence industry jobs in the U.S., help win Ukraine the war and build up its own defence against future Russian attack, and all funded by the aggressor — Russia," Ash suggested.

A precarious future

Whatever the outcome of Tuesday's vote, analysts agree that Ukraine faces a precarious future amid waning Western support and funding fatigue.

Tim Willasey-Wilsey, senior associate fellow at the Royal United Services Institute, a defense think tank, commented that "the immediate peril" for Ukraine comes from the 2024 U.S. presidential election.

"The forthcoming presidential election in the US represents the point of maximum danger. A win by Donald Trump could see him placing a phone call to Russian President Vladimir Putin as early as 6 November. Any such call would set expectations of a negotiated settlement, with discussions possibly beginning in the early months of 2025," he said.

In any such deal, Willasey-Wilsey said that Ukraine's President Volodymyr Zelenskyy would be unlikely to secure the recovery of Russian-occupied peninsula Crimea and the Donbas region in eastern Ukraine, or to receive reparations for the massive damage to his country. It's also likely that a negotiated settlement would stipulate that Russian officials are not put on trial for alleged war crimes.

A bigger blow could be that a peace deal puts an end to reaching the holy grail for Ukraine — future NATO membership.