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A conservative group planned Monday to launch a high-dollar ad campaign in support of President Trump’s Supreme Court pick, as part of a projected $10 million push to get the nominee confirmed.

As both sides gird for a costly and confrontation battle before that nominee is even announced, the conservative Judicial Crisis Network made clear they consider this fight even more substantial than the one to confirm Justice Neil Gorsuch.

“This is an even bigger fight than the one to get now-Justice Gorsuch confirmed and therefore the budget will be at least $10 million to confirm the president’s next great justice,” Carrie Severino, chief counsel with JCN, said in a statement to Fox News.

For starters, Judicial Crisis Network is launching a $1.4 million ad buy on national cable and digital, with a particular focus on four states: Alabama, Indiana, North Dakota and West Virginia. The ad is expected to feature an introductory bio on the president’s yet-to-be-named Supreme Court nominee.

The campaign is set to launch “as soon as the nominee is announced,” according to Judicial Crisis Network.

The president plans to announce his choice to replace Justice Anthony Kennedy on the bench on Monday night at the White House.

“I have long heard that the most important decision a U.S. President can make is the selection of a Supreme Court Justice—Will be announced tonight at 9:00 P.M.,” Trump tweeted Monday morning.

The decision marks his second Supreme Court appointment, after having won confirmation for Justice Neil Gorsuch last year. This year's battle could be even harder-fought by the advocacy groups competing to sway key senators.

The states targeted by JCN are represented by Democratic senators considered to be potential swing votes: Alabama's Doug Jones, Indiana's Joe Donnelly, North Dakota's Heidi Heitkamp and West Virginia's Joe Manchin.

The ad follows JCN’s initial million-dollar ad campaign, “Another Great Justice,” which was launched the day after Kennedy announced his retirement from the high court last month.

With its new ad, JCN will have spent a total of $2.4 million in national cable, broadcast and digital to support the president’s pick for the high court.

While the group plans to spend much more, the Democrat-tied Demand Justice has already spent millions to preemptively oppose the president’s Supreme Court choice -- and pressure moderate GOP senators.

Demand Justice, a liberal group led by the former press secretary for Hillary Clinton’s presidential campaign, Brian Fallon, has launched a reported $5 million campaign targeting GOP Sens. Susan Collins of Maine and Lisa Murkowski of Alaska, in an aggressive push to sway moderate senators of both parties to oppose the eventual nominee.

“The next SCOTUS pick should await the next election, but McConnell won’t wait,” Fallon tweeted last week. “The future of the Court for the next 40 years –and thus the fate of abortion rights, and the ACA—may be decided in the next 3 months.”

The ads, on both sides of the aisle, signal a deep partisan divide—suggesting whoever Trump announces will receive staunch support from Republicans and be roundly opposed by Democrats.

Sources who spoke to Trump on Sunday morning told Fox News that the president’s top two choices are appellate court judges Brett Kavanaugh and Thomas Hardiman, though a Republican source late Sunday said that appellate court Judge Amy Coney Barrett was still in the running. Judge Raymond Kethledge also is considered a finalist.

Hardiman was the runner-up when Trump nominated Neil Gorsuch to replace the late Justice Antonin Scalia last year. Hardiman also has a personal connection to the president, having served with Trump’s sister on the 3rd U.S. Circuit Court of Appeals in Philadelphia.

Any nominee could face a tough confirmation process—with Republicans holding a razor-thin majority in the Senate. Republicans currently have 51 votes, and would ordinarily need 50 to confirm Trump’s nominee, with Vice President Pence voting to break a tie. But with Sen. John McCain, R-Ariz., out battling cancer, Democrats could block the nomination with a single Republican defection.

Should Barrett secure the president’s nomination, Collins could be that defection, as she has expressed concerns about Barrett to the White House.

But Manchin, Heitkamp and Donnelly voted to confirm Gorsuch along with 51 Republicans last year, and potentially could offset any GOP defections.

Senate Majority Leader Mitch McConnell, R-Ky., who consistently touts the confirmation of Gorsuch, suggested last week that Democrats were “ready to fight no matter who the nominee is.”

“And look,” McConnell said on “Fox News @ Night” last week, “the stakes are big.”

Fox News’ John Roberts, Samuel Chamberlain and Andrew O’Reilly contributed to this report.