- Former Massachusetts Gov. Bill Weld announced he will challenge President Donald Trump in the 2020 Republican primary.
- Weld had been touring many states with an exploratory committee.
- In 2016, Weld was the Libertarian Party's vice presidential nominee with his running mate, former New Mexico Gov. Gary Johnson.
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Former Massachusetts Gov. Bill Weld announced Monday he will challenge President Donald Trump in the 2020 Republican primary.
Weld officially becomes the first serious challenger to Trump's re-election campaign, which has been growing staff and raising large sums of donations in recent months.
"Ours is a nation built on courage, resilience, and independence. In these times of great political strife, when both major parties are entrenched in their 'win at all cost' battles, the voices of the American people are being ignored and our nation is suffering," Weld said in a statement Monday.
"It is time for patriotic men and women across our great nation to stand and plant a flag. It is time to return to the principles of Lincoln - equality, dignity, and opportunity for all. There is no greater cause on earth than to preserve what truly makes America great. I am ready to lead that fight."
Immediately following the announcement, Weld will travel to New Hampshire to make several campaign stops this week.
Weld had been previously exploring a potential presidential run, which he announced in February.
In 2016, Weld ran as the vice presidential nominee on the Libertarian Party ticket with former Gov. Gary Johnson.
Weld's entrance into the 2020 race could damage Trump's re-election chances. While the Trump campaign has sizable assets both in terms of infrastructure and finances, sitting presidents who face serious primary challenges often go on to lose in the general election.
Still, the Trump campaign is in prime position to fend of challenges. The president's re-election campaign announced Monday a massive war chest, having raised $30 million on its own in the first quarter of 2019 and $76.1 million combined with the Republican National Committee's haul.
The RNC dismissed Weld's challenge in a statement to INSIDER soon after the announcement.
"President Trump enjoys unprecedented support among Republicans," the RNC said. "He has already delivered a long list of incredible accomplishments for conservatives and the country. The RNC and the Republican Party are firmly behind the president. Any effort to challenge the president's nomination is bound to go absolutely nowhere."
At the same time, the Democratic field of candidates looking to unseat Trump is rapidly growing, with 18 lawmakers, governors, and outsiders having jumped into the race.