Harris says the cemetery is "not a place for politics" in her first remarks on the incident.

The US presidential hopeful appeared to signal his support, placing him at odds with other Republicans.

Some of the vice-president's views have changed since she first entered politics.

Debates have played a major role in her political career, but the showdown on 10 September will have the highest stakes yet.

The former president appeared open to voting to pass a referendum that would expand abortion rights, but faced pressure from conservatives.

There was no new ammunition for Republicans, but it highlighted the challenge she faces in pitching herself as a change candidate.

The vice-president and Democratic nominee tells CNN her "values have not changed" despite shifts on key issues.

The campaign pledge comes after Democrats have hammered his administration's effect on abortion and reproductive rights.