WASHINGTON — A federal judge on Wednesday allowed President Donald Trump, at least temporarily, to move forward with his effort to exert federal control over mail-in ballots ahead of the midterm elections.

The decision by Boston-based U.S. District Court Judge Indira Talwani to lift an injunction that applied nationwide follows a Supreme Court decision favoring Trump in a similar case on Monday.

But with litigation moving swiftly, there remains a strong chance that key aspects of Trump’s mail-in ballots executive order will be blocked at some stage, possibly as soon as later on Wednesday.

The executive order directs the U.S. Postal Service to, among other things, track mail-in ballots and potentially reject those submitted by people not on a federal list of eligible voters.

Multiple legal challenges to the proposal, which conflicts with the states’ traditional role in administering elections, are pending.

Trump has frequently criticized mail-in ballots even though they are widely used by Republicans and Democrats all across the country.

The Supreme Court on Monday lifted a nationwide injunction that had blocked the executive order in a case brought by California and 22 other states. That ruling left in place a second injunction in a separate case brought by various groups including the League of Women Voters, which Talwani lifted on Wednesday. She is overseeing both cases.

The Supreme Court, divided 6-3, concluded that Talwani had acted too hastily in ruling on the executive order, but did not weigh in on whether the underlying proposal or the Postal Service regulation to implement it is lawful.

The Trump administration argued that the injunction in the League of Women Voters case should be lifted in light of the Supreme Court ruling, as the same logic applies in both cases.

Talwani reluctantly agreed, while making it clear that the challengers have “substantial arguments that might persuade the Supreme Court to reach a different result” if the litigation ultimately returns to the justices.

Lawyers in the cases brought by the League of Women’s Voters and the states are both set to challenge the regulation.

Talwani, appointed by President Barack Obama, in a separate order issued on Tuesday said that the Trump administration violated her original injunction because it had moved forward with issuing the Postal Service regulation despite her instruction not to do so. But she elected not to impose any sanctions on the government, saying only that she was “identifying the violation.”