Trump Photo:VCG

 US President Donald Trump's campaign on Sunday appealed part of a ruling that clears the way for the battleground state of Pennsylvania to certify Democratic President-elect Joe Biden as the winner of the ­November 3 election.

In a court filing, the campaign asked the US third ­Circuit Court of Appeals to review a decision by US District Judge Matthew Brann.

The campaign filed a suit earlier this month, asking Brann to halt the state from certifying the results.

Brann's ruling, issued on Saturday, described the case as based on "strained legal arguments" and "speculative accusations."

In a court filing, the Trump campaign said it was focusing its appeal on the "narrow" question of whether Brann improperly refused to let them amend their lawsuit a second time.

For Trump to have any hope of overturning the election, he needs to reverse the outcome in Pennsylvania.

Brann had denied a request by the campaign to add back allegations it dropped from the case, including a claim that its due process rights were violated.

Under Pennsylvania law, the candidate who wins the popular vote in the state gets all the state's electoral votes.

Trump's lawyer Rudy Giuliani said on Saturday that Brann's quick ruling would help them get the case "expeditiously to the US Supreme Court."

The lawsuit before Brann was filed on November 9 and had alleged inconsistent treatment by county election officials of mail-in ballots. Some counties notified voters that they could fix minor defects such as missing "secrecy envelopes" while others did not.

Brann said in his decision that he had "no authority to take away the right to vote of even a single person, let alone millions of citizens."

Brann, nominated by former president Barack Obama, is a Republican and, according to his biography, a member of the Federalist Society, a group of conservative and libertarian lawyers, law students and scholars.

The Trump campaign and its supporters have filed dozens of lawsuits in six closely contested states. 

The campaign's only victories extended the Election Day voting hours at a handful of polling places in Nevada and set aside some provisional ballots in Pennsylvania, according to court records.