At the time of writing, Brent was trading at $99.42 a barrel and West Texas Intermediate at $91.242. Both had risen from Thursday’s close after reports of fresh attacks on tankers in the strait.

Reuters reported at least five vessel incidents in the Persian Gulf since Sunday. Commercial traffic remains under threat even as crude shipments through the Strait of Hormuz have recovered. The attacks and doubts about the prospects for peace between the United States and Iran have helped limit the decline in oil prices.

ING commodity analysts wrote in a Thursday note that, “In the absence of escalation, the oil market is likely to continue to slowly give back the risk premium it built in recent months, with oil flows from the Persian Gulf holding up well.” They added that escalation remains another possibility for President Trump, one that could keep prices elevated.

KCM Trade chief analyst Tim Waterer told Reuters that oil would likely remain supported on dips until there is “a credible path to safer, cheaper transit through the Gulf,” and could move sharply on headlines about escalation. FXPro senior market analyst Alex Kuptsikevich said the Republicans’ midterm defeat does not rule out further conflict. He pointed to 2006, when Democrats took control of Congress during the Iraq war, but U.S. policy in the Middle East under President George W. Bush did not change.