Sara Gideon concedes to Susan Collins in competitive Maine Senate race

Sara Gideon conceded to Sen. Susan Collins Wednesday afternoon in the fierce Senate race in Maine.

The Democratic challenger delivered a four-minute concession speech that was live-streamed.

"Mainers rallied around our campaign in a way I've never seen before. And, while we came up short, I do believe Mainers in every corner of this state are ready to continue to work together to make a difference," said Gideon, 48, the Democratic speaker of the Maine House of Representatives.

In her speech, Gideon said she spoke to Collins and "congratulated her on winning this election."

"And I told her that I will always be available to help serve the people of Maine," Gideon said. "Ultimately, that's why I entered this race, and it's why I got involved in public service in the first place."

This will be the fifth Senate term for Collins, 67, who was considered one of the most vulnerable senators up for reelection. The senator, who was least aligned with President Donald Trump among her Republican colleagues, was not endorsed by the president.

Her win strengthens the Republican party's chances of retaining control of the Senate.

Gideon was slightly favored to win Maine's Senate election by FiveThirtyEight. She had won endorsements from groups that had previously backed the incumbent, including the Human Rights Campaign.

Throughout the campaign, Gideon, and the Maine Democratic Party, tried to tie Collins to both President Trump and Majority Leader Mitch McConnell. It was a prevalent narrative during the candidates' final debates.

During those debates, Collins was focused on Maine and what she says she'd delivered for the state she's been representing in the Senate since 1997, including her work on the Paycheck Protection Program. She even took some digs at Gideon, a Rhode Island native, for not being a born-and bred-Mainer.

Before speaking to supporters Wednesday afternoon, Collins confirmed to ABC News that she got a "very gracious call" from Gideon.

Maine's Secretary of State office told ABC News it gives each municipality two days to count the votes before the office calls any race, so an official call on the Senate race may not come until then.

In the presidential race, ABC News projects that three of Maine's electoral votes will go to former Vice President Joe Biden and one will go to Trump.

In her speech, Gideon spoke to the challenges that the country faces and the work left to "deliver the change that we need."

"While this election may be over, we have to work together to build a better future, one where everyone has access to health care they can afford. Where we tackle our climate crisis head-on, and where we restore our economy by prioritizing hardworking people and their families," she said.

Here is a transcript of Gideon's concession speech:

"Good afternoon. Thank you all for tuning in.

Over the past 16 months, I've traveled across this incredible state of ours and met with so many of you. From the workers at Portsmouth Naval Shipyard in Kittery to the nurses and doctors at the hospital in Calais, you've invited me into your homes, spoken with me in your workplace and stopped me at the store to share the challenges that you face.

At our 'Suppers with Sara' across the state, you let me share my ideas, and you asked me tough questions that gave us the opportunity to think about what leadership for Mainers should look like, and how we could build a better future for Maine families together.

I have been humbled, touched and inspired by you and your stories each and every day. I listened to you. I heard about the challenges you face, and promised to take your experiences with me so that we could deliver the change that we need.

We brought people together and put forward a set of ideas and vision to move this state and its people forward. Mainers rallied around our campaign in a way I've never seen before. And, while we came up short, I do believe Mainers in every corner of this state are ready to continue to work together to make a difference.

Just now, I spoke with Sen. Collins. I congratulated her on winning this election. And I told her that I will always be available to help serve the people of Maine. Ultimately, that's why I entered this race, and it's why I got involved in public service in the first place.

My parents taught my sisters and me that we should always look at the world around us and figure out how we could each make a difference for people. It's what we've instilled in our kids, and it's why I entered public service in the first place.

Whether it was on the town council, in the State House, as speaker or on this campaign, I have always worked to find our shared goals, and to bring people together to get things done for Mainers. That work doesn't stop today for any of us. In fact, it's more important now than ever before.

The challenges that we are facing as a state and as a country are some of the greatest that we've seen in our lifetime. While this election may be over, we have to work together to build a better future, one where everyone has access to health care they can afford. Where we tackle our climate crisis head-on, and where we restore our economy by prioritizing hardworking people and their families.

I am proud of the campaign we ran. And regardless of the result, together we built a movement that will help us make progress for years to come. Thousands of Mainers stood together, making phone calls, knocking on doors, talking to their friends and neighbors about what better leadership looks like. And that's what we need to continue to do, and I will continue to stand with you in that work.

So, let's get some rest. Let's reflect on the work that we've done over the past 16 months, and then, let's get back to work.

I thank you for the hospitality, generosity and commitment that you've shown me throughout this campaign. It means the world to me and my family, and I won't ever forget it."

ABC News' Quinn Scanlan and Stephanie Ramos contributed to this report.