President Donald Trump says he doesn't believe self-made billionaire media proprietor and philanthropist Oprah Winfrey will run for president in 2020 but he expressed confidence that he would defeat her. "Oprah will be lots of fun," Trump said at the White house Tuesday. "I don't think she's going to run." WATCH: Trump on Oprah presidential run Winfrey, 63, is not running — at least, officially. But her Sunday night speech at the Golden Globe awards show unleashed immediate and intense media speculation about a candidacy in 2020, presumably as a Democrat. “I don’t know if he saw it," deputy White House spokesman Hogan Gidley said on Monday responding to a reporter’s question about whether Trump saw Winfrey’s impassioned speech in which she made no mention of him or the presidency. However, her remarks about being raised in poverty, empowerment of women and support for the press (under constant criticism by Trump), quickly prompted even some conservative political figures to speak positively of her as a potential candidate. Winfrey, when asked backstage if she planned to run for president, replied, "I don't. I don't." But some close to her were quoted Monday saying she is thinking about it. Her long-time partner, Stedman Graham, was quoted Sunday evening telling The Los Angeles Times, “It's up to the people. She would absolutely do it.” In a television interview early last year, Winfrey indicated that Trump’s election had changed her mind about whether she lacked experience for America’s highest office. But in another TV interview in October, she dampened speculation, stating, “There will be no running for office of any kind for me.” Winfrey, as was the case for Trump before being elected president, has never held public office. In the past, Trump has spoken positively of Winfrey. In a 1999 television interview when he said he was thinking about running for president the following year (although he did not), Trump declared, “Oprah would always be my first choice” for a running mate," adding, “she’s brilliant” and “a very exceptional woman.” Winfrey endorsed Democratic Sen. Barack Obama of Illinois when he first ran successfully for the U.S. presidency in 2008, and former U.S. Secretary of State Hillary Clinton in her losing 2016 campaign against Trump. No clear Democratic front-runner has emerged to challenge Trump in 2020, with the immediate political focus in the U.S. on November's congressional elections, when the 435-member House of Representatives will be up for election, along with a third of the 100-member Senate. In the months after the congressional elections, halfway through Trump's four-year term, Democratic presidential challengers are likely to begin announcing their candidacies to run against him. Ken Bredemeier contributed to this report.