On February 15, 2019, Weld officially announced the formation of an exploratory committee in preparing to run for the 2020 Republican Party presidential primaries. Soon after, Weld began making appearances in media, appearing on CNN on Presidents Day 2019, stating he believed Trump has "showed contempt for the American people". He appeared on both Bloomberg News and MSNBC's Morning Joe the next day. On Morning Joe, he criticized Donald Trump as president, with a focus especially on what he labeled bad foreign policy in regards largely to North Korea and Russia. On April 15, 2019, Weld officially announced his candidacy for the Republican nomination during an appearance on The Lead with Jake Tapper. Weld's campaign was managed by Jennifer Horn, the former chair of the New Hampshire Republican State Committee and also includes Stuart Stevens, a top strategist for Mitt Romney's 2012 presidential campaign. On March 18, 2020, Weld suspended his campaign.
Political positions
Abortion
In May 2019, Weld described himself as "the most pro-choice person you’re ever going to meet." He said that recent abortion laws passed by states, such as Alabama's Human Life Protection Act, left him feeling "terrible". As governor of Massachusetts, Weld introduced a bill increasing ease of access to abortion in the state. In the 1990s, he publicly fought for removing anti-abortion language from the Republican Party platform, despite opposition from social conservatives.
Drugs
Weld believes that drug use should not be a criminal offense. Weld has also called for federal decriminalization of marijuana and the lowering of the drinking age.
Weld has described himself as fiscally conservative, with goals of reducing spending and balancing the budget. For this reason, he has been described as a "classic conservative". He has proposed to drastically reduce military spending, withdraw American forces from foreign engagements, and refocus American politics on domestic issues primarily.
Education
Weld has been a supporter of charter schools, having established the first twenty-five Massachusetts charter schools as governor.
Environment
Weld challenged Trump on the issue of climate disruption, saying that he had made no effort to combat the effects of global warming. "We've got the polar ice cap that's going to melt with devastating consequences if we don’t get carbon out of the atmosphere," Weld told "America's Newsroom," noting that he would plan ahead for an "environmental catastrophe." On Monday, April 15, 2019, Weld formally announced his candidacy for President of the United States on The Lead with Jake Tapper. Weld received 1.3% of the vote in the Iowa caucuses and one pledged delegate on February 3.
Impeachment
On October 26, 2019, it was reported that while speaking at Tufts University, Weld suggested that Trump might not even appear on the 2020 ballot. Weld noted that choosing a secret vote about impeachment is an option available to the Senate, and that former Senator Jeff Flake suggested that a secret vote in the process could shield senators effectively from adverse political reactions by the "Trump base", thereby freeing them to vote for conviction. Weld estimated that under those circumstances, 30 to 35 votes to convict would be attained easily and that only 20 were needed.