Sources close to the Vice President told The Washington Post that if the war drags on for months, it could significantly damage the GOP's next nominee. 

Vance has told his closest advisers that he has not yet decided whether to run in 2028 because of his upcoming child. 

One source said Vance's fourth child, due this summer, has also made him rethink his presidential ambitions. 

He and Usha Vance want to see how another baby affects their lives before committing to jumping back on the campaign trail. 

Vance, who started his political career as a vocal advocate against prolonged military conflict in the Middle East, is now noticeably quiet as Trump pushes forward with his war against Iran. 

Pressure has mounted on the Vice President in recent days following the dramatic resignation of former Counterterrorism Director Joe Kent.

Before Kent's announcement, in which he publicly criticized Trump and claimed the war was launched because of Israel, Vance tried to persuade him not to turn his departure into a public feud. The effort ultimately failed.

At least 13 US troops have been killed and over 200 injured since the start of Operation Epic Fury. 

The conflict has led to a global oil crisis as gasoline has surged to an average of $3.90 per gallon from $2.90 before the conflict began three weeks ago, while the Strait of Hormuz - through which a fifth of the world's oil flows - remains blockaded by Iranian mines and missiles.

A year ago, after Trump stormed back into the Oval Office, Vance was viewed as the likely successor to Trump in 2028. 

However, Trump's foreign policy shift over the last several months has highlighted the hawkish influence of Marco Rubio. 

The Secretary of State was notably at Trump's side in the makeshift Situation Room at Mar-a-Lago in January during the military operation against Venezuela that led to the capture of dictator Nicolas Maduro.

He was again next to the President at his Florida estate at the start of Operation Epic Fury, as missiles rained down over Tehran.

Vance was not present at either meeting, fueling speculation about a potential rift between him and Trump.

Earlier this month, the President admitted that Vance was initially 'maybe less enthusiastic' and 'philosophically a little bit different' regarding the war on Iran. 

Vance's odds of becoming the GOP nominee have also collapsed on betting markets such as Kalshi. Near the end of last year, Vance held approximately a 54 percent chance of becoming a nominee. 

Now, however, Rubio is nearly tied with him at 31 percent while Vance maintains a 38 percent chance of becoming the nominee in 2028, according to Kalshi.