"Love the fact that the small groups of protesters last night have passion for our great country. We will all come together and be proud!" Trump tweeted early on Friday.
On Thursday night, the president-elect had posted: "Just had a very open and successful presidential election. Now professional protesters, incited by the media, are protesting. Very unfair!"
Mostly peaceful and orderly protests took place in at least eight cities following the Republican businessman's defeat of Democrat Hillary Clinton in Tuesday's election. Demonstrators have voiced concern Trump would harm Americans' civil rights.
Trump's critics worry that his often-inflammatory campaign rhetoric about immigrants, Muslims, women and others - combined with support from the Ku Klux Klan and other white supremacists - could spark a wave of intolerance against minorities.
East Coast protests took place on Thursday in Washington, Baltimore, Philadelphia and New York, while on the West Coast, demonstrators rallied in Los Angeles, San Francisco and Oakland in California, and Portland, Oregon.
After Clinton conceded defeat early on Wednesday, Trump took a far more conciliatory tone than he had often displayed during his campaign, promising to be a president for all Americans. His campaign rejected a Klan newspaper endorsement days before the election, saying Trump "denounces hate in any form."
But civil rights groups and police reported an uptick in attacks on minority groups, some by people claiming to support Trump.
More anti-Trump demonstrations were planned for the weekend. Trump takes office on Jan. 20, succeeding President Barack Obama.
Thursday's gatherings were generally smaller in scale and less intense than Wednesday's, and teenagers and young adults again dominated the racially mixed crowds.
Republican National Committee Chairman Reince Priebus on Friday acknowledged the tight race with Clinton, but said anti-Trump protesters had to accept the election results. He pointed to Trump's call for unity and meeting with Obama and Republican leaders as reasons for reassurance.
"Everyone needs to just take a deep breath, take the weekend ... count our blessings, and let's come back on Monday," Priebus said.
MARCH FROM THE WHITE HOUSE
Police set up security barricades around two Trump marquee properties that have become focal points of protests - his newly opened Pennsylvania Avenue hotel near the White House and the high-rise Trump Tower in Manhattan, where he lives.
About 100 protesters marched from the White House, where Trump had his first transition meeting with Obama on Thursday, to the new Trump International Hotel several blocks away.
At least 200 people rallied there after dark, many chanting, "No hate! No fear! Immigrants are welcome here!" and carrying signs with such slogans as "Impeach Trump" and "Not my president."
"I can't support someone who supports so much bigotry and hatred. It's heart-breaking," said Joe Daniels, 25, of suburban Alexandria, Virginia.
Two Trump supporters stood off to the side carrying signs reading: "All We are Saying is Give Trump a Chance". Protesters in Portland threw objects at police and damaged cars in a dealership lot, police said, while local media reported graffiti on cars and buildings along with smashed storefront windows.
Portland police on Friday said they had arrested at least 26 people after using pepper spray and rubber bullets to try to disperse the crowd. They declared the protest, lasting into Friday morning, a riot.
"Many in crowd trying to get anarchist groups to stop destroying property, anarchists refusing. Others encouraged to leave area," the Portland Police Department said on Twitter.
ARRESTS, MARCHES
At least 35 protesters were arrested in downtown Los Angeles after blocking traffic and sitting in the street, local media said. A smaller band of demonstrators briefly halted traffic on a busy Los Angeles freeway before police cleared them.
In San Francisco, more than 1,000 high school students walked out of classes on Thursday morning to march through the financial district carrying rainbow flags representing the lesbian, gay, bisexual and transgender communities, Mexican flags, and signs decrying Trump.
Dozens in Minneapolis marched onto Interstate 94, blocking traffic for at least an hour as police stood by.
In Baltimore, about 600 people marched through the downtown Inner Harbor area, with some blocking roadways by sitting in the street, police said. Two people were arrested.
In Denver, a crowd that media estimated to number about 3,000 gathered on the grounds of the Colorado state capitol and marched through downtown in one of the largest of Thursday's events. Hundreds demonstrated through Dallas.
(Reporting by Gina Cherelus in New York and Ian Simpson in Washington; Additional reporting by Jon Herskovitz in Austin, Texas, Donna Owens in Baltimore, Curtis Skinner in San Francisco, Steve Dipaola in Portland, Susan Heavey in Washington and Brendan O'Brien in Milwaukee; Writing by Scott Malone and Steve Gorman; Editing by Jeffrey Benkoe and Howard Goller)
