Retired longtime state Supreme Court Chief Justice Bill Waller Jr., son of a former governor, is planning a gubernatorial run this year as a Republican, sources involved in his planning confirmed Wednesday.

One of Waller's main campaign themes is expected to be that he is the only Republican candidate who can beat Democratic Attorney General Jim Hood — who remains very popular in an otherwise deep red state — in the race for governor.

Republican Lt. Gov. Tate Reeves, already with $7 million in his campaign war chest, has been the presumptive GOP front-runner. But Reeves has trailed Hood in past and recent polling and is unpopular with some segments of the establishment state GOP and hard-line conservatives. Another Republican in the race, freshman state Rep. Robert Foster, a farmer from Hernando, lacks the name recognition and fundraising capacity of Reeves and Waller.

Many political observers believe Waller's entrance into the GOP primary might prompt Republican state Sen. Chris McDaniel, a favorite of tea party conservatives, to enter what's becoming a crowded primary.

Waller, 67, is son of the late Gov. Bill Waller Sr., a Democrat who served from 1972 to 1976. Waller recently said he was not ruling out a run for governor, but was leaning against it.

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"I'm not closing any doors at this time," Waller told the Clarion Ledger in November as he announced his retirement from the bench. "I will decide after I retire Jan. 31."

There had been much speculation that Waller might run for governor as an independent — and at least one recent poll posed that question to voters. The poll showed Waller tracking only 9 percent, taking votes evenly from Hood and Reeves, and with only about 50 percent name recognition. But Waller supporters questioned the poll, saying it included too many young respondents and that older voters — more likely to turn out for a gubernatorial election — know the Waller name well from his years on the bench and his father's term as governor.

Mississippi Republican Party Chairman Lucien Smith on Wednesday said he doesn't believe Waller entering the race will alter the eventual outcome he predicts: A Republican winning the governorship.

"Our focus at the party is preparing for November, and the voters will choose in the meantime who they want to be our nominee," Smith said. "What won't change is that they are going to vote for a Republican governor in November. Policy will be the focus, and do they want a governor who supports Republican policy, or do they want a Democrat who supports policies of higher taxes, more regulations and less freedom? Whoever voters choose at the end of the day will be a Republican."

Reeves campaign spokesman Parker Briden in a statement said, "We've always expected multiple primary challengers — every open governor's race has plenty."

"Tate Reeves has held the line against raising taxes or expanding Obamacare and Mississippi voters overwhelmingly want that kind of strong leader as governor," Briden said. "That’s why he has an historic level of grassroots and financial support."

Foster in a statement said Waller entering the race, "shows a healthy democratic process for our state and that, as I've said all along, voters are looking for another alternative to 'the next guy in line.'"

"I look forward to joining Justice Waller on the campaign trail, as Judge Waller and his family come from a long line of public service to our state," Foster said.

A Hood campaign spokesman declined comment until Waller qualifies or makes a public announcement. The deadline for qualifying for statewide races is March 1.

Longtime Mississippi politico and political science professor Marty Wiseman said Waller has "a heck of a pedigree" and will be a serious contender.

"I don't know how much money he's got to run on, but he may be starting down $7 million," Wiseman said. "... But Waller is going to be serious and have his contributors ... We've heard many Republicans say they are not going to vote for Tate Reeves, but I've always said that when they get in the ballot booth, they will see that R by his name and come home. Now Waller is going to cut off some of that vote ... He's creating an alternative for folks who want to vote Republican but are disinclined to vote for Tate Reeves. They now will have a legitimate option."

Waller resigned from the state high court at the end of January, after 21 years on the court and 10 years as chief justice.

He oversaw modernization of the court and expansion of its electronic record system, expansion of state drug courts and changes in criminal court rules that allowed defendants to go before judges more quickly.