While Tuesday is election day, early voting has already seen a record 54 million people cast ballots across the US. (EPA Images pic)WASHINGTON: Republicans made a final push Sunday to prevent a predicted thumping in US midterm elections where Democrats are gunning to win control of Congress and impose a first political check on President Donald Trump's unprecedented pursuit of power.

Polls show Democrats are all but certain to take the majority from Republicans in the House of Representatives in Tuesday's vote and have a real shot at winning the Senate.

But after a decade of Trump defying political gravity and two years of a second presidency in which he has ridden roughshod over every norm, Democrats remain nervous.