US Democratic presidential frontrunner Hillary Clinton

Democratic front-runner Hillary Clinton on Wednesday eked out a narrow win in the Kentucky primary over Bernie Sanders who kept his underdog campaign alive with a decisive win in Oregon while on the Republican side Donald Trump moved closer to being declared the party nominee.

Clinton, 68, squeezed out a cliffhanger victory over Sanders in Kentucky, a result that keeps her on track to win the nomination but also highlights deep divisions in the party.

The former secretary of state won the state by half a percentage point with nearly all the votes counted. Sanders, meanwhile, won the Oregon Democratic primary with several US networks calling the Pacific northwest state for the 74-year-old.

Sanders — the proponent of Democratic socialism — crushed Clinton, bagging 53 per cent votes to her 47 per cent. However, despite the series of defeats in the Democratic primaries over the past few weeks including Oregon and a very close finish in Kentucky, Clinton still appears to be on her way to clinch the nomination of the Democratic party for the November general elections.

This is mainly because she is way ahead of Sanders in the delegate count and requires less than 100 more delegates to reach the magical figure of 2,382 delegates to become the Democratic presidential nominee.

“We just won Kentucky! Thanks to everyone who turned out. We’re always stronger united,” Clinton tweeted as she was declared the winner by just 1,923 votes.

Such a narrow win, CNN said derailed some of the momentum of the Clinton Campaign. However, Clinton herself has set her sights on the November presidential elections. In a tweet and an email, she urged her supporters to help raise funds to defeat Trump in November polls.

Meanwhile, on the Republican side, 69-year-old Trump garnered nearly two-thirds of the total votes polled in Oregon, further consolidating his position as the presumptive presidential nominee.

Trump, who joined politics less than a year ago, has defeated 16 top Republican leaders to emerge as the presumptive nominee.

With a win in Oregon, Trump has 1,171 delegates in his kitty and needs just 66 delegates to reach the 1,237 figure to officially clinch the nomination.

This is now considered a mere formality given that he is the only one left in the race. Nearly 350 delegates are still to be awarded from the remaining primaries.

“I look so forward to debating Crooked Hillary Clinton! Democrat Primaries are rigged, e-mail investigation is rigged — so time to get it on!” Trump said in a tweet soon after being declared the winner of the Oregon primary.