AUGUSTA, Maine — UPDATE: A spokesperson for Sen. Collins' campaign released the following statement about Gideon's announcement:

“The Democrats have a year-long competitive primary ahead -- they will not be picking a nominee until June of 2020," Kevin Kelley said. “One of the reasons why Senator Collins has been so effective is that she has more seniority than any U.S. Senator from Maine over the past 70 years. She will continue to build on her record of extraordinary accomplishments for the people of Maine.”

Maine democratic Speaker of the House of Representatives, Sara Gideon, officially announced her plans to run against Sen. Susan Collins Monday morning.

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In a video posted to Twitter, Gideon slammed Collins for her controversial vote to confirm Brett Kavanaugh to the Supreme Court and boasted her own work to promote job training and prescription drug reform in Maine. 

Rumors of a possible run have been swirling over the last couple of weeks after an article was published in the HuffPost.

Incumbent Sen. Collins' approval rating has dropped in recent polling since the Kavanaugh hearings.

RELATED: Mainers react to Gideon running for Senate

According to a Critical Insights tracking poll released last month, Sen. Collins has an approval rating of 41% — down 10 points from last fall's 51% and 17 points from last spring's 58%.

A spokesperson responded to the poll upon its release, calling it an outlier.

"We don’t put much stock in any one poll," Annie Clark said in a statement. "But I would note that the methodology of this one -- including the fact that it was done over several weeks and that it included a significant online component -- is different than you traditionally see with public polls."

RELATED: Poll: Collins' approval down 17 points from last spring

Collins' office declined to comment specifically on Gideon's announcement Monday.

Gideon's campaign website also launched Monday emphasized she "always stood up for a woman's right to choose."

"As newly appointed Supreme Court justices threaten the future of Roe vs. Wade and state legislatures across the country pass laws banning abortion in almost all circumstances, Sara has led the fight to make sure women in Maine remain in control of their health care decision," the website said.

Gideon, a prominent progressive in state politics and long rival of former Republican Governor Paul LePage, is serving her second term as Speaker and a fourth term representing Freeport and Pownal in the House.

She lives in Freeport with her husband and three children and agreed to speak with NEWS CENTER Maine on Monday.

"Talking to Mainers, listening to Mainers, continuing to build on the really strong work that we've done in the State House," Gideon said regarding the reason for her campaign.

Gideon said that when it comes to Sen. Susan Collins, she believes it's time for a change in the U.S. Senate. 

"When I think about Susan Collins and when she first went to Washington, I didn't think she was like other people in Washington," said Gideon. "I'm not sure that's true anymore, and I'm not sure she is putting the interests of Mainers ahead of special interests."

Some of that rationale comes from Collins' vote in fall 2018 to confirm Supreme Court Judge Brett Kavanaugh -- a decision that she calls a "punch to the gut" to families in Maine.

"She has had some decent pro-choice votes before, but this one -- a lifetime appointment -- that really made a difference," Gideon said about Collins. "She left us. She disappointed us, and she did the wrong thing."

Gideon finished third in the 2018 Democratic primary for governor. 

Not all fellow politicians are supporting Gideon's run for Senator, citing the caucus and taxes among reasons they do not support her.

"From leading a corrupt caucus, to her inability to work across party lines even though she touted her ability to do so, Sara Gideon is just another far left Democrat who won't rest until she can give Mainers’ voices and votes to New York," said RNC Spokesperson Nina McLaughlin in a statement. "It's no wonder she's Chuck Schumer's pick for the Senate -- if elected, Gideon would be nothing but a rubber stamp for Schumer’s obstructionist caucus."

"Sara Gideon has done nothing but work against Mainers’ best interests," said a separate statement from Maine GOP Chair Dr. Demi Kouzounas. "From supporting taxes that would devastate Maine families, like a tax on heating oil and gas, Sara Gideon is eyeing Maine families’ bank accounts to fund her extreme policy proposals. From welfare for non-citizens, to trying to give away Mainers’ voices and votes, Sara Gideon only works for two entities: herself and New York."

Gideon is not the only one throwing their hat into the ring. 

Democrat Betsy Sweet announced her plans to challenge Collins in 2020 earlier this month.

RELATED: Progressive announces bid to challenge Susan Collins in 2020

Collins, who was born and raised in Caribou, was just ranked as one of the most bipartisan members of the U.S. Senate and has never missed a vote in her 23 years in office.

RELATED: Collins casts 7,000th straight vote as reelection race looms