U.S. Rep. Diane Black, R-Tennessee, is entering the 2018 race for governor of Tennessee, ending months of speculation and adding a deep-pocketed candidate who is widely considered a front-runner to an already-crowded Republican field.

Black, a staunch conservative from Sumner County who is in her fourth term representing Tennessee's 6th Congressional District, will formally announce her candidacy in an online video to be released Wednesday.

In the video, Black discusses her rise from humble beginnings while labeling herself as a conservative fighter ready to take on liberals.

"Most people in politics say the right things, but they never fight for the right things," Black says in the 90-second clip. "They're too meek or maybe even too weak ... I don't back down. Maybe's it's because I grew up in a family where we had nothing or maybe it's because I was a single mom working in the night-shift as a nurse. It's just how I'm wired."

Black, 66, joins the race with the most name recognition of the five leading Republican contenders, polling suggests, and a track record of championing conservative causes in Congress.

Black enjoys ties to both establishment and tea party Republican politics, a strong fundraising prowess and the ability to self-finance some of her campaign.

She touts her pro-life record and how she fought against a GOP-led state income tax plan when she was a state lawmaker.

"I believe in secure borders and tough choices in cutting spending and beating the liberals instead of caving into them," she says.

Her seven years in Washington could lead to attacks from her opponents and Republican primary voters dismayed with the Beltway. And though popular among many tea party-aligned Republicans, Black will face other candidates who pull from the same base. While well-known in Middle Tennessee, Black is not as familiar in East and West Tennessee.

Impact on the primary

Black's entrance dramatically alters the GOP primary, set for August 2018.

Other declared Republican candidates are Knoxville entrepreneur Randy Boyd, Franklin businessman Bill Lee, House Speaker Beth Harwell and state Sen. Mae Beavers. Former Nashville Mayor Karl Dean is the only declared Democratic candidate, but House Minority Leader Craig Fitzhugh has indicated he plans to run.

Beavers, Harwell and Black are seeking to become the first female governor in state history.

Black's announcement rounds out the top-tier candidates expected to vie for the Republican nomination seeking to succeed Gov. Bill Haslam.

A Vanderbilt University poll released in late May showed Black, at 49 percent of registered Tennessee voters, had a considerable lead in name recognition among those expected to run.

In a race anticipated to be the most expensive in Tennessee history, Black’s financial firepower will allow her to compete among a field of Republicans that includes multiple millionaires.

More:How the 2018 Tennessee governor's race is shaping up as the state's most expensive ever

Black is one of the wealthiest members of Congress. In 2013, the assets of Black and her husband David Black, who in November retired as CEO of Aegis Sciences Corp., were valued at nearly $150 million.

Lee, chairman of Williamson County-based Lee Co., and Boyd, former commissioner of the Tennessee Department of Economic and Community Development, have collectively pumped $3.4 million of their own money into their campaigns, according to their latest disclosures.

“We always run campaigns that are good, strong campaigns,” Black said after handily defeating former state Rep. Joe Carr last August. “We don’t give up. We work hard until the last minute. We knock on doors. And we fight back. When we get punched, we punch back."

Black, who frequently supports President Donald Trump, became the first female chair of the House Budget Committee in February after then-U.S. Rep. Tom Price, R-Ga., was appointed secretary of Health and Human Services.

Personal life

Raised in Baltimore public housing, Black moved to a small, rural town in Maryland when she was 5. She became the first person in her family to go to college when she graduated from community college in Maryland with an associate degree in nursing.

She married David in 1980 and later moved to the Nashville area, where she earned her nursing degree from Belmont University. They have three children and six grandchildren.

Working as a nurse in Gallatin, Black was first elected to the state House in 1998. She successfully ran for the state Senate in 2004, serving six years before mounting a congressional bid in 2010.

In a nationwide election that saw a wave of tea party Republicans enter Congress, Black eked out 31 percent in the GOP primary against former Rutherford County GOP Chairwoman Lou Ann Zelenik and state Sen. Jim Tracy.

Because of her previous time as a state lawmaker, Black already has a Tennessee campaign committee, but the account only has $14,000. Cash on hand for her congressional committee is $33,280, but she is not allowed to use federal money in a state race.

Though Black's campaign team has not been announced, she's hired OnMessage, a consulting group co-founded by Brad Todd, a past Black campaign aide. Republican operative and former Lt. Gov. Ron Ramsey's chief of staff Lance Frizzell is an adviser.

Reach Joel Ebert at jebert@tennessean.com or 615-772-1681 and on Twitter @joelebert29.

Diane Black

Age: 66

Occupation: Nurse

Home: Gallatin

Education: Anne Arundel Community College (associate degree); Belmont University (Bachelor of Science in Nursing)

Family: Husband David, three children, six grandchildren

Religion: Community Church