Trump has delegates to clinch nomination, CBS News estimates

CBS News estimates that Donald Trump has reached the 1,237 delegates needed for the Republican nomination, based on the support of both bound and unbound delegates.

He will continue to add to his total with delegates from the upcoming primaries and any additional support from unbound delegates.

Trump addressed the latest delegate count at a North Dakota press conference Thursday.

"The folks behind me got us right over the top, from North Dakota, so North Dakota made a big statement and I just really appreciate it," Trump said. "We will not forget it."

The good news for Trump was tempered by continuing problems for his campaign. Those include the abrupt departure of Trump's political director and continuing resistance by many Republican leaders to declare their support for his upstart candidacy.

It takes 1,237 delegates to win the Republican nomination. With 303 delegates at stake in five state primaries on June 7, Trump will easily pad his total, avoiding a contested convention in Cleveland.

Trump does not become the nominee until delegates vote at the convention. Until then, he continues to be the presumptive nominee.