If courts in the US decide to take up the lawsuits filed by the Trump campaign and intervene to review results, it will not be the first time that the presidential race has ended in a legal battle.

In 2000, the White House contest between Republican George Bush and Democrat Al Gore boiled down to one state: Florida. With Bush ahead by just 537 votes, and with problems with the state’s punch-card ballots, the Gore campaign sought a statewide recount. The Bush campaign appealed the case to the US Supreme Court, which ruled to effectively block the full recount, handing Florida — and the election — to Bush.

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Experts, however, say that legal recourse is only practical if focused on a real problem and the vote gap is narrow. If the margin separating candidates in that state is two or three percentage points — say, a 100,000 vote difference in Pennsylvania — “that’s pretty difficult to be litigating at the end of the day,” said Derek Muller, a law professor at the University of Iowa, reports AFP. However, said Muller, “if it comes down to one state, then I would expect really serious litigation.”

As Democratic nominee Joe Biden bagged 253 electoral college votes, inching closer to the halway mark of 270, the Republicans braced for a legal showdown. Trump’s campaign announced a recount demand in Wisconsin and lawsuits in Michigan and Pennsylvania, three states critical to winning the presidency.

US networks have called Michigan and Wisconsin for Biden, while Pennsylvania remains open. Late Wednesday the Trump campaign filed suit in a fourth battleground, Georgia, as the president’s lead there shrank to less than a percentage point.,Trump’s behavior raised the specter of the election ultimately being decided, as in 2000, by a Supreme Court ruling on how states can tally votes.

The Trump campaign lawsuits attack a unique aspect of the 2020 election — that millions of voters cast mail-in ballots because of the coronavirus pandemic. The COVID-19 threat forced states to promote mailed ballots and change rules on how they would be collected, verified and tabulated. That included extending the periods for receiving ballots, due to an overburdened US Postal Service, adding time for vote-counting.

The Republicans, according to AFP,  say some of those changes were decided or implemented improperly and in ways that favour Democrats. In Pennsylvania, the Trump campaign said it would join an existing Republican suit over the state’s deadline extension for receiving mail-in ballots.,If successful, they have the potential to disqualify tens of thousands of ballots that arrived after November 3.

The Pennsylvania Supreme Court ruled that the extension legal, and last week the US Supreme Court declined to get involved. But the high court left the door open for a post-election challenge. Trump’s campaign also said it was suing to have Pennsylvania ballot counting temporarily halted, alleging the process was being hidden by Democrats. In Philadelphia the counting was live-streamed. And they sued over changes to voter identification — made to adjust to the pandemic — saying it violated the election code, AFP adds.

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In Michigan, the Trump campaign sued to halt ballot counting saying they were not given “meaningful access.”

The Georgia suit wants counties to “separate any and all late-arriving ballots from all legally cast ballots” that arrived by the 7:00 pm Election Day deadline, Trump deputy campaign manager Justin Clark said.