Liberal Senator Bernie Sanders slammed President Donald Trump as a 'pathological liar' and a 'terrible example' for his seven grandchildren ahead of speculation he may make another presidential bid in 2020.

'I've got four kids, seven grandchildren - young kids - we try to raise our kids to be honest and treat other people with respect and compassion and what kind of terrible example, regardless of your political views - doesn't matter whether you are conservative or progressive - you want your kids to be honest and decent. What kind of terrible example is this person in the White House giving to our children?' Sanders said at the rally in Columbia, South Carolina, on Saturday.

The senator was speaking at a conference of Our Revolution SC, the state chapter of the organization that spun off from his unsuccessful bid for the Democratic presidential nomination in 2016.

Bernie Sanders slammed President Donald Trump as a 'pathological liar' and a 'terrible example' for his seven grandchildren

Sanders is one of several Democrats considering a challenge to President Trump in 2020

The appearance was billed as a 'Medicare for All' rally.

And while Sanders did talk about health care, he sounded more like a presidential candidate, thanking his supporters from 2016, throwing red meat remarks to his liberal base, and attacking the president.

'I know this is going to shock you, but Donald Trump lied,' Sanders said of the president's policies as the crowd roared with laughter and applause.

There were nearly 1,000 people there to cheer Sanders on, according to the Associated Press.

The senator is on a campaign swing for the 2018 midterms, but the trip is filled with hints of what may come in 2020 - taking him through the early voting states of South Carolina, Iowa, and Nevada.

He's also making a stop in California - whose state is increasing in importance for the 2020 primary. California's primary date is in the process of being moved up on the calendar, giving it more weight in picking the Democrats' nominee, and Sanders' liberal policies could play well in that state.

Sanders, an independent senator from Vermont who caucuses with Democrat, also criticized Trump as an 'embarrassment' and a 'pathological liar.'

'What is an embarrassment to me,' Sanders said at his South Carolina appearance, 'is that we have a president who is a pathological liar.'

'There is no politician in history who doesn't stretch the truth in order to make his or her point, that's politics but we have never had a president who lies all the time and it's quite possible he doesn't even know the difference between a truth and a lie,' he noted.

He also said it was 'criminal' the way the president has acted in regard to the climate.

'All he is doing is standing with the fossil fuel industry,' Sanders said.

But Sanders said there is one 'core' problem with Trump that concerns him the most.

'Presidents of the United States - whether liberal or conservative - understood that the major responsibility of the president of he United States is to bring people together,' he said.

'Today we have us a president who for cheap political gain - or what he perceives as political gain - is trying to divide us up by the color of our skin, by our gender, by where we were born and by sexual orientation, or by the religion that we practice. It is an absolute disgrace,' Sanders added.

Sanders isn't the only potential presidential candidate to show up in South Carolina.

Senators Kamala Harris of California and Cory Booker of New Jersey have visited South Carolina ahead of 2020 speculation

Former Vice President Joe Biden and former New York City Mayor Michael Bloomberg have also visited South Carolina

Sanders is on a 2018 campaign swing for Democrats including this stop in Michigan

Former Vice President Joe Biden, Sen. Kamala Harris, Sen. Cory Booker, and former New York Mayor Michael Bloomberg have all visited the state.

Sanders has said he'll make a decision about 2020 after the November midterms.

In his remarks on Saturday, he pointedly thanked out those who supported him in his last bid.

'It was no easy task because everyone knows this was a state we were not going to do well in,' he said.

In the 2016 South Carolina Democratic primary, Sanders received a scant 26 percent to Hillary Clinton's 74 percent.

'So there are progressives in South Carolina! I was told that nobody would come out to a meeting like this,' Sanders told the cheering crow. 'Thank you all very much for being here.'