WASHINGTON/NEW YORK (REUTERS) - US Republican Donald Trump has dismissed his vulgar sexual comments about women that surfaced on a video as "locker room talk", but his explanation did little to soothe the queasiness of Ms Esther Rosser, a 71-year-old grandmother from Virginia.

"I know he apologised, and all you can do is apologise, but he could have said more," said Ms Rosser, who has voted Republican her whole life but decided this weekend that she would support Mr Trump's rival for president, Democrat Hillary Clinton.

"He disrespected us," she said of Mr Trump, referring to women in general.

Her misgivings echoed many of the sentiments expressed by more than two dozen women voters interviewed by Reuters who, as recently as September, had not decided whether they would support Mr Trump or Mrs Clinton in the Nov 8 US election.

In the informal survey conducted by phone the day after Sunday's presidential debate, many women said they were appalled by the 2005 video in which Mr Trump bragged about kissing and groping women without consent. The video surfaced on the Washington Post's website on Friday afternoon.

Several of the voters also said they disliked the Republican presidential candidate's strategy of highlighting the infidelities of Mrs Clinton's husband Bill Clinton in an effort to defend his own conduct, or shift attention away from it.

"I didn't like the fact that he was attacking Hillary on things her husband did," said Ms Connie Sasso, a 66-year-old retiree from Missouri. "It's wrong - it's just wrong."

FLOORED, DISGUSTED

In the second presidential debate with Mrs Clinton on Sunday in St Louis, Missouri, Mr Trump said he was embarrassed by the video but dismissed his comments as "locker room talk".

He also accused Mrs Clinton of attacking women who had alleged sexual misconduct by her husband, who was president from 1993 to 2001.

Mr Trump's criticism of Mr Bill Clinton's infidelities drew applause from supporters at a Monday rally he held in Pennsylvania. But Mr Trump, whose core voters are overwhelmingly male, has struggled to appeal to women, who made up 53 per cent of the US electorate in the 2012 election.

If Mr Trump is unable to narrow the gender gap, he will be unable to overcome Mrs Clinton's lead in the polls.

"I can't with good conscience vote for someone with that kind of mindset to the presidency," said Ms LeighAnn Chase, a 27-year-old nursing student from Lakeland, Florida.

As a woman, she was "floored" by Mr Trump's comments, and disgusted that others would seek to justify them, said Ms Chase, a registered Republican who said she is now backing Mrs Clinton.

Ms Patsy Bennewise, 58, of North Little Rock, Arkansas, never voted for Mrs Clinton's husband during the nearly 10 years he was her state's governor. But her streak of never voting for a Clinton is set to end in November when she plans to cast her ballot for the Democratic candidate.

She said of Mr Trump: "He's turned the presidential election into a mockery."

SOME STAY ON FENCE

Not all undecided women voters contacted by Reuters came out against Mr Trump. Ms Amy Fryzelka, a 37-year-old tutor from Kansas City, Missouri, said she thought his comments were "horrible" but she believed his personal life would not influence how he would govern.

She said she is leaning towards the Republican candidate because she believes Mrs Clinton is too deceptive. "I'd prefer not to vote for either of them, really," Ms Fryzelka said.

Ms Jane Simmons, 78, of Sterling Heights, Michigan, also said she would rather not vote for either Mrs Clinton or Mr Trump.

Ms Simmons, whose mail-in ballot arrived on Friday, hours before she and other Americans learnt of Mr Trump's lewd comments, said the video led her to consider backing Mrs Clinton.

"This is an indication of what the man is, although it was a decade ago, I don't think he changed very much," she said. "I don't believe he's got a conscience."

For Ms Rosser, the Virginia grandmother, the decision to cast her vote for Mrs Clinton came when her 14-year-old granddaughter asked her to explain why Mr Trump would say the things he said in the video.

"He's not a good role model for kids," she said.