AUGUSTA — Democratic U.S. Senate candidate Troy Jackson has raised $2 million since securing his party’s nomination on Saturday, his campaign announced Monday.

Jackson, 58, a former Maine Senate president, officially became the Democratic choice to face Republican Sen. Susan Collins in November following a Saturday convention.

“I’m humbled beyond words by the tens of thousands of people who have stepped up to become part of this campaign,” Jackson said in a statement. “Every contribution — whether it was five dollars, twenty dollars, or more — is a vote of confidence in the working-class movement we’re building together.”

According to the Jackson campaign, 58,000 donors have now contributed to his run for the Senate. The $2 million reported on Monday is in addition to $1 million he raised prior to the convention, his campaign confirmed on Monday.

Despite the new cash infusion, Jackson still trails Collins by a wide margin in fundraising.

Collins has raised nearly $19 million and currently has $11 million in cash on hand, according to the latest Federal Election Commission filing.

Money raised by candidates is expected to be a small slice of the overall spending on the Senate race, which has national implications for which party controls the chamber.

Spending by outside groups and political action committees run by Washington leaders will likely far outpace money raised and spent by the candidates themselves.

For example, just minutes after Jackson won the nomination, the Senate Leadership Fund announced “a six-figure ad campaign” critical of Jackson.

The group, which is spending money in Senate races across the country to protect the Republican majority, has said it will spend over $42 million on the Maine Senate race.

Early polling shows a statistical tie between Jackson and Collins. Jackson leads 49% to 46%, according to the University of New Hampshire Pine Tree State Poll. The margin of error is nearly 3%.

In June, Jackson finished third in the race for governor and at one point was one of 13 Democrats who declared an intent to run for the U.S. Senate.

But following county meetings earlier this month, Jackson won an overwhelming number of delegates to the convention, clearing his path to victory.

On Saturday in Bangor, Jackson received 566 delegate votes, while Saundra Pelletier, a health care executive and native of Caribou, received five votes.

The special convention concluded a process that began July 10 when military veteran and oyster farmer Graham Platner dropped out of the race following an allegation of sexual assault.

Platner denies the allegation but was forced to drop out when national Democrats pulled their funding and when he faced calls from the Maine Democratic Party to end his campaign.

Collins is seeking her sixth term to the Senate. Maine is one of a handful of states targeted by Democrats seeking to regain a majority in the Senate.