As GOP aides on the Senate Judiciary Committee pore over Judge Sonia Sotomayor’s record, Senate Republicans are preparing their first wave of attacks on President Barack Obama’s nominee to the Supreme Court and plan to roll out their preliminary “concerns— this weekend, GOP aides said Thursday.

Although outside conservative organizations began hammering at Sotomayor’s record as a judge on the 2nd U.S. Circuit Court of Appeals and her public statements within hours of Obama’s announcement Tuesday, Senate Republicans have largely kept their powder dry until now.

According to GOP leadership aides, Judiciary ranking member Jeff Sessions’ (R-Ala.) staff on the committee have quietly been preparing a list of potential issues and concerns for Republicans to raise in the coming weeks in advance of Sotomayor’s confirmation hearings.

Beginning with appearances on this Sunday’s talk shows by Sessions, Senate Minority Leader Mitch McConnell (R-Ky.) and National Republican Senatorial Campaign Committee Chairman John Cornyn (Texas), Republican leaders will begin “the next phase in raising concerns— about Sotomayor, one aide explained.

Republicans are still working out what specific concerns they will raise, but the source said lawmakers will likely avoid “the top-line criticisms— of conservatives, particularly any attacks that could be seen as overtly playing the race card or taking politically motivated shots at Sotomayor.

Meanwhile, Sen. Pat Roberts (R-Kan.) this week indicated he is unlikely to vote for Sotomayor’s nomination based on his opposition to her circuit court nomination in 1998.

Roberts said in an interview with KCMO Talk Radio 710 that he does not “plan to vote for her,— his office said.

The GOP leadership aide said that while McConnell and other leaders are continuing to counsel their members to withhold public statements on how they plan to vote on the nomination, it is likely that more Members who voted against Sotomayor in 1998 will reaffirm their opposition in the coming days and weeks.