Montana Gov. Steve Bullock (D) announced Monday that he is ending his longshot bid for president.

“I entered this race as a voice to win back the places we lost, bridge divides and rid our system of the corrupting influence of dark money,” Bullock said in a statement. “While the concerns that propelled me to enter in the first place have not changed, I leave this race filled with gratitude and optimism, inspired and energized by the good people I’ve had the privilege of meeting over the course of the campaign.”

“While there were many obstacles we could not have anticipated when entering this race, it has become clear that in this moment, I won’t be able to break through to the top tier of this still-crowded field of candidates,” he added.

The 53-year-old struggled to raise money and register in the polls, managing to meet the qualification thresholds for only one Democratic National Committee debate in July.

He’s the third Western governor or former governor to drop out of the 2020 race after struggling to build a national profile and donor base against well-known alternatives like former Vice President Joe Biden and Vermont Sen. Bernie Sanders. Former Colorado Gov. John Hickenlooper dropped out in August to instead run for the Senate. His departure was followed quickly by that of Washington Gov. Jay Inslee, who is seeking reelection.

Bullock also ruled out running for Senate, a move that congressional Democrat leaders have reportedly urged in recent months.

“While he plans to work hard to elect Democrats in the state and across the country in 2020, it will be in his capacity as a governor and a senior voice in the Democratic Party — not as a candidate for U.S. Senate,” Bullock spokesperson Galia Slayen said.

Bullock served as attorney general of The Treasure State prior to being elected governor in 2013.

The Associated Press contributed to this report.