"WASHINGTON -- National Republicans are already lining up plans for an aggressive ad campaign in Minnesota targeting Sens. Amy Klobuchar and Al Franken when President Obama announces his pick to fill the Supreme Court vacancy.

Klobuchar and Franken, both Democratic members of the Senate Judiciary Committee, have been outspoken about filling the vacancy left open in February after the sudden death of conservative Justice Antonin Scalia. The two senators say an Obama nominee deserves a nomination hearing and, ultimately, a vote in front of the full Senate before Obama leaves office in January 2017.

Senate Republicans and conservative outside groups have pushed back, saying an Obama nominee doesn't deserve a hearing because Obama only has ten months left in office. They prefer to hold hearings and a vote on a nominee when a new president is sworn in next year.

The White House has said a nomination to fill the vacancy could be announced within a month.

The Republican National Committee said Monday they will target Klobuchar and Franken with calls to their "swing" voters, radio ads using quotes from Democrats, and "targeted digital ads on social media" to swing voters on the topic once a nominee is announced.

"The RNC will dedicate staff and resources to thoroughly vetting the president's nominee and launch a messaging effort against Democrats to make them explain why they do not want adhere to the Biden Rule and give the American people a voice in this process," a spokesman said Monday.

Republicans often cite statements that now Vice President Joe Biden made in 1992 about Supreme Court vacancies during election years. At the time, there were rumors an 83-year-old justice was going to retire and Biden hoped to discourage that during an election year. There was no vacancy on the Court when Biden made the comments.

On Monday, Franken said, "facts can be stubborn things."

"The fact of the matter here is that there is a long bipartisan tradition of giving full and fair consideration to Supreme Court nominees. It's important that we don't forget that the American people have spoken. Twice. President Barack Obama was elected and reelected by a solid majority of the American people," he said, in a statement. "The president of the United States has the constitutional responsibility to nominate a justice to the Supreme Court."

Klobuchar, in an email, said the Republicans would be more useful if they spent their time holding a fair hearing.

"It is up to their members as to whether they want to vote for a nominee, but the nominee deserves a hearing and a vote," she said.