Wisconsin Republican Sen. Ron Johnson will seek reelection and part ways with a 2016 promise to only serve two terms, according to multiple online reports.

The Associated Press, which spoke with Republicans who have knowledge of Johnson's plan, reported Johnson "has decided to seek reelection to a third term" and "could announce as soon as early next week."

Another report from Politico stated Johnson is "expected to run for reelection this year," while CBS News echoed similar claims in its reporting on the matter, citing a source familiar with Johnson's decision.

Sen. Ron Johnson

Senator Ron Johnson of Wisconsin along with other Senate Republicans slam CDC's new mask recommendations.  (Getty Images)

CBS News reported Johnson is likely to "kick off his campaign next week."

TWO GOP SENATORS HAVE YET TO SAY IF THEY'RE RUNNING FOR REELECTION IN NOVEMBER

Two weeks ago, while speaking to Fox 11 News in Green Bay, Wisconsin, Johnson said his reelection "decision will be made here shortly."

The Senate contest in Wisconsin – a key battleground state that President Biden narrowly carried in the 2020 election – is one of a handful of contests that could ultimately decide which party controls the Senate.

Johnson vowed as he ran for reelection in 2016 to only serve two terms, but with the Democrats controlling the White House and both houses of Congress, the senator says times have changed.

"That’s certainly one of the things that’s weighing on my mind. If you’re in a position to offer some improvement, help the situation out, would you just walk away?" Johnson told Fox 11 News.

United States Sen. Ron Johnson (Photo by STR/NurPhoto via Getty Images)

The Senate is currently split 50-50 between the two major parties, but Democrats hold a razor-thin majority due to the tie-breaking vote of Vice President Kamala Harris through her constitutional duty as president of the chamber.

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Should he announce reelection efforts, Johnson – an ardent supporter of former President Trump – would have a good chance of winning reelection in Wisconsin, a state Biden won by less than a percentage point in 2020. Trump narrowly won Wisconsin in 2016.

Johnson has been sharply critical of the Biden administration, saying last month during an appearance on "Hannity" that calling the administration "incompetent" would be "too kind."

"It's accurate to call the Biden administration incompetent, but that's way too kind," Johnson said as he discussed the administration's policies. "These are their policies, the results of their policies were obvious from the start, and now Americans are waking up to it."

In this June 26, 2019 file photo, Sen. Ron Johnson, R-Wis., chairman of the Senate Committee on Homeland Security and Governmental Affairs, speaks during a hearing on border security, on Capitol Hill in Washington. (AP Photo/Patrick Semansky)

Johnson stirred controversy last year as he called the Capitol rioters people who "love this country." He has attacked the "unequal application of justice" he sees between the suspects involved in the Jan. 6 U.S. Capitol riot and those involved in Antifa and Black Lives Matter protests in cities like Philadelphia, Portland, New York City and Washington over the past year that devolved into criminal activity.

Johnson defeated three-term Democratic Sen. Russ Feingold in the Tea Party fueled GOP wave election of 2010 and then edged Feingold again in a 2016 rematch.

Fox News reached out to Johnson's office but did not receive an immediate response.

Fox News' Paul Steinhauser contributed to this article.