Trump celebrates decision that could secure his party's re-election months before voting takes place

Donald Trump has celebrated after a court decision that will cost Democrats dearly in the upcoming midterm elections.

A referendum in the state of Virginia allowed the government there to redraw its district boundaries in a way that benefited Democrats.

The state currently has six Republicans in the House of Representatives and five Democrats.

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But the redraw approved by voters would give Democrats the edge in 10 of the 11 seats.

That state's Supreme Court has knocked back that map overnight on procedural grounds in a 4-3 decision.

"Huge win for the Republican Party, and America, in Virginia," Trump wrote on Truth Social today.

"The Virginia Supreme Court has just struck down the Democrats' horrible gerrymander."

Drawing congressional districts in a way that deliberately swings the outcome is known in the US as gerrymandering. 

Unlike in Australia, most US states allow state legislators to draw congressional districts, as well as their own state-level districts.

The party in power in that state then has the power to draw districts in a way that favours them.

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Multiple states have been redrawing their maps months out from the midterm elections, which Democrats have been favoured to win.

The gerrymandering has been stepped up in the past week, after the US Supreme Court overturned a law that required states to draw districts for non-white voters if it was feasible to do so.

That law, signed in 1964, was designed to stop gerrymandering in the south in a way that would lock black politicians out of ever getting elected.

Since it was overturned last month, several Republican-controlled legislatures have begun dismantling black-majority districts.

In Tennessee yesterday, Republican legislators split the city of Memphis into three largely rural districts.

"For too long, Tennessee politics has been dominated by cosmopolitan communists and race hustlers imposing their corrupt will on a deeply rural and conservative state," Republican Congressman Andy Ogles said.

"The General Assembly's constitutional redrawing of Federal Districts affirms a foundational truth: Tennessee must be represented by Tennesseans, not socialist democrats."

After the law was passed, Democratic state representative Justin Pearson set fire to a Confederate flag in protest.

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"These maps are racist tools of white supremacy at the behest of the most powerful white supremacist in the United States of America, Donald J Trump," he said.

The redrawing of the map also secures the re-election prospects of Ogles, who is facing a serious challenge from the Democratic mayor of the city of Columbia, Chaz Molder.

The new gerrymander drew Columbia out of Ogles' district.

Legislators in Louisiana, South Carolina, Alabama and Mississippi are also considering maps that would replace black Democrats with white Republicans.

In the US south, political opinions are divided starkly on racial lines, with white voters overwhelmingly backing Republicans and black voters overwhelmingly backing Democrats.

Maps in Texas and Florida have also been redrawn to benefit Republicans, and in California to benefit Democrats.

Republicans currently hold a majority of just a handful of seats in the House of Representatives.

Polling shows Democrats are likely to outdo Republicans in November's elections.

READ MORE: Trump celebrates Supreme Court decision that could sway elections for years to come

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