Trump supporters' optimism starting to wear off: Poll

More than six months into Donald Trump's young presidency, optimism among his core supporters and American voters at large is starting to fade, a new poll has revealed.

After Trump's surprise victory in November, six in 10 American voters said they were mostly optimistic about his presidency. But that number slipped to 52 per cent in March and 43 per cent currently, CNN quoted the Quinnipiac University poll as saying on Saturday.

A majority of registered voters (53 per cent) now say they are mostly pessimistic about the next few years of Trump's time in office.

Optimism for the Trump presidency among Republican voters dropped from a virtually unanimous 96 per cent in January and March down to 84 per cent now, with one in six Republicans now saying they are mainly pessimistic about his tenure, the poll showed.

In another poll conducted by Gallup, whites without a college degree have also shown a slight but steady decline, CNN reported.

Trump started at 62 per cent approval with this key group when he took office in January, but has since slipped from 56 per cent in May to 54 per cent in June and to 53 per cent in July.

Still, Republicans have mostly stayed on board in Gallup's approval ratings over the last six months, which means Trump's low approvals are actually largely driven by Democrats and independents.